Biomedical subjects

D M Ilstrup

Publications and source records attributed to D M Ilstrup.

At least 73 records · Page 4Linked to original sources

PubMed1997

Bone-graft augmentation for acetabular deficiencies in total hip arthroplasty. Results of long-term follow-up evaluation.

The results of 102 consecutive primary and revision total hip arthroplasties performed with bone-grafting for acetabular bone deficiencies were reviewed at an average of 10.2 years (range, 4-18.6) after surgery. Ninety-one percent had structural bone defects and 57% had underlying developmental dysplasia of the hip. Overall acetabular revision rates for aseptic loosening were 8% at 5 years and 26% at 10 years. In addition, in the patients with developmental dysplasia who had primary hip arthroplasties, acetabular revision rates for aseptic loosening were 3 and 18% at 5 and 10 years, respectively. Ninety-six percent of all uninfected grafts incorporated. Bulk grafts fared better than particulate grafts. No difference in failure rate was noted between primary and revision hip arthroplasty, type of deficiency, or amount of graft coverage. Although early results are encouraging, acetabular failure increased significantly with longer follow-up evaluation; however, graft incorporation was successful and facilitated subsequent revision surgery.

Acetabulum↗

PubMed1997

Seroconversion to human herpesvirus 6 following liver transplantation is a marker of cytomegalovirus disease.

Human herpesvirus 6 (HHV-6) infection is common after transplantation; HHV-6 is known to interact with other viruses and induce immunosuppression. Whether HHV-6 plays a role in the occurrence of cytomegalovirus (CMV) infection after transplantation was investigated. In a cohort of 247 liver transplant recipients, HHV-6 seroconversion was identified as a significant risk factor for development of symptomatic CMV infection (P < .001), including CMV organ involvement (P < .001), even in the presence of the other significant risk factors: D+/R- CMV serologic status (P < .001) or use of OKT3 after transplantation (P = .002). Subgroup analysis indicated that HHV-6 seroconversion was significantly associated with symptomatic CMV infection in the D+/R+ but not in the D+/R- CMV serologic group (P < .001 and P = .11, respectively). These results indicate that HHV-6 seroconversion is a marker for CMV disease after transplantation and suggest that additional studies using more sensitive diagnostic techniques are warranted to determine the relationship between HHV-6 and CMV infection after transplantation.

Adult↗

PubMed1997

Analysis of 281,797 consecutive blood cultures performed over an eight-year period: trends in microorganisms isolated and the value of anaerobic culture of blood.

The results for 281,797 blood culture sets of specimens collected from adult patients at the Mayo Clinic over an approximately 8-year period (1 November 1984 through 30 November 1992) were analyzed in order to determine whether there were differences in the types of microorganisms isolated over this time and to assess the usefulness of anaerobic culturing of blood. Each blood culture set consisted of two aerobic blood cultures (Septi-Chek [Becton Dickinson, Sparks, MD] and Isolator [Wampole Laboratories, Cranbury, NJ]) and one anaerobic culture (nonvented tryptic or trypticase soy broth [NVTSB; Difco Laboratories, Detroit, or Becton Dickinson]). The relative frequency of isolation of aerobic and facultatively anaerobic gram-positive bacteria and obligately anaerobic bacteria increased over the second half of the 1984-1992 surveillance period. The value of the NVTSB anaerobic blood culture was demonstrated for diagnosing bloodstream infections caused by certain facultatively anaerobic bacteria in addition to obligately anaerobic bacteria and supported the inclusion of the NVTSB anaerobic blood culture as a standard part of the three-component blood culture set used at this institution.

Adult↗

PubMed1997

Staphylococcus aureus prosthetic joint infection treated with debridement and prosthesis retention.

Debridement and retention of the prosthesis was the initial treatment modality in 30 patients with 33 Staphylococcus aureus prosthetic joint infections (PJIs) who presented to the Mayo Clinic between 1980 and 1991. Treatment failure, defined as relapse of S. aureus PJI or occurrence of culture-negative PJI during continuous antistaphylococcal therapy, occurred in 21 of 33 prosthetic joints. The 1-year and 2-year cumulative probabilities of treatment failure were 54% (95% confidence interval [CI], 36%-71%) and 69% (95% CI, 52%-86%), respectively. A median of 4 additional surgical procedures (range, 1-9) were required to control the infection in the 21 prosthetic joints for which treatment failed. Prostheses that were debrided >2 days after onset of symptoms were associated with a higher probability of treatment failure than were those debrided within 2 days of onset (relative risk, 4.2; 95% CI, 1.6-10.3). These data suggest that debridement and retention of the prosthesis as the initial therapy for PJI due to S. aureus is associated with a high cumulative probability of treatment failure and that the probability of treatment failure may be related to the duration of symptoms.

Adult↗

PubMed1997

Clinical comparison of BACTEC 9240 plus aerobic/F resin bottles and the isolator aerobic culture system for detection of bloodstream infections.

The Plus Aerobic/F resin bottle of the BACTEC 9240 automated blood culture system (Becton Dickinson Diagnostic Instrument Systems, Sparks, Md.) was compared with aerobic culture of the Isolator system (Wampole Laboratories, Cranbury, N.J.) for the detection of bloodstream microorganisms from 6,145 blood cultures collected from adult patients with suspected septicemia. The BACTEC resin bottles were incubated for 7 days, and the sediment from the Isolator tube was inoculated to sheep blood and chocolate agars which were incubated for 72 h and to inhibitory mold, brain heart infusion, and Sabouraud agars which were incubated for 21 days. A total of 622 microorganisms were recovered from 583 blood cultures. The BACTEC resin bottle recovered statistically significantly more pathogens overall than the Isolator system (P = 0.0006). When individual pathogens isolated from either system for a 7-day study period were assessed, it was determined that the BACTEC resin bottle detected statistically significantly more isolates of Staphylococcus aureus (P = 0.0113) and coagulase-negative Staphylococcus spp. (P = 0.0029) than the Isolator system. The BACTEC resin bottle also detected statistically significantly more bloodstream infections (septic episodes) caused by coagulase-negative Staphylococcus spp. (P = 0.0146). The Isolator system recovered statistically significantly more contaminants overall (P < 0.0001), and among this group of microorganisms, recovered statistically significantly more Bacillus spp. (P < 0.0001), coagulase-negative Staphylococcus spp. (P < 0.0001), and viridans group Streptococcus spp. (P = 0.0156). The Isolator system detected statistically significantly more isolates of Histoplasma capsulatum (P = 0.004), but all of these isolates were detected at > or = 7 days of incubation of fungal plates, i.e., after the system to system comparison study period (7 days). In blood culture sets which produced growth of the same pathogen in both systems, there was a statistically significant difference in median time to detection for all pathogens combined favoring the BACTEC resin bottle over the Isolator tube (P < 0.05). When assessing individual microorganisms, the median times for detection of S. aureus, Enterococcus spp., and Pseudomonas spp. were all statistically significantly less for the BACTEC system (P < 0.05). The BACTEC instrument had 79 (1.3%) false positive signals. The BACTEC system required less processing time than the Isolator system and eliminates the hands-on time for detection of positive cultures required with the Isolator system.

Adult↗

PubMed1997

Detection of colorectal polyps with CT colography: initial assessment of sensitivity and specificity.

PURPOSE: To estimate the sensitivity and specificity of computed tomographic (CT) colography in detection of colorectal polyps and to compare these findings with those at axial CT. MATERIALS AND METHODS: In 70 consecutive patients, CT colography and colonoscopy were performed. Helical axial CT images and CT colographic images (multiplanar two- and three-dimensional endoluminal images) were evaluated separately by two radiologists blinded to results from colonoscopy and other imaging studies. Findings were compared with those at colonoscopy, which was the standard. RESULTS: The sensitivity and specificity for the two observers with CT colography averaged 75% and 90% in patients with adenomas 10 mm in diameter or larger, 66% and 63% in patients with adenomas 5 mm in diameter or greater, and 45% and 80% for patients with adenomas less than 5 mm in diameter, respectively. Sensitivity and specificity with axial CT were lower than those with CT colography (58% and 74%, respectively) in patients with adenomas 10 mm in diameter or larger. CONCLUSION: Compared with axial CT, CT colography appears to have superior sensitivity and specificity in detection of clinically important colorectal adenomas. Early performance of CT colography seems promising for detection of colorectal polyps 5 mm and larger.

Adenoma↗

PubMed1997

Effect of the elevated-rim acetabular liner on loosening after total hip arthroplasty.

Elevated-rim acetabular liners recently were shown to be associated with improved stability of total hip prostheses in a large clinical series. However, the effect of this design on loosening remains unknown. To address this question, we reviewed the results of 5167 primary and revision total hip arthroplasties that had been performed at our institution from September 1, 1985, through December 31, 1991; 2469 of the acetabular components had an elevated-rim liner (10 degrees of elevation), and 2698 had a standard liner. Five-year follow-up data were available for 1237 hips (174 that had an elevated-rim acetabular liner and 1063 that had a standard acetabular liner). The cumulative probability of revision because of loosening of the implant was estimated as a function of time since the operation with use of the Kaplan-Meier survivorship method. The five-year probability of survival of the acetabular component was 98.8 per cent (95 per cent confidence interval, 97.9 to 99.6 per cent) for the prostheses that had an elevated-rim liner and 98.3 per cent (95 per cent confidence interval, 97.7 to 99.0 per cent) for those that had a standard liner (p = 0.87). The effect of the elevated-rim acetabular liner on the probability of revision because of loosening of the acetabular or the femoral component was analyzed for several subgroups: components inserted with cement, components inserted without cement, primary total hip arthroplasties, revision total hip arthroplasties, male patients, and female patients. With the numbers available, no significant differences were found in the probability of survival of the acetabular or the femoral component in any of the subgroups. Theoretical considerations suggest that the geometric design of the elevated-rim acetabular liner may have biomechanical characteristics that predispose the implant to early loosening. However, our initial review of the results of total hip arthroplasties after a mean follow-up period of five years (range, 0.25 to ten years) failed to demonstrate any difference in the cumulative probability of revision because of loosening of the implant. Continued surveillance is warranted and ongoing.

Acetabulum↗

PubMed1997

Complications after concomitant bilateral total knee arthroplasty in elderly patients.

OBJECTIVE: To determine the risks associated with performance of bilateral total knee arthroplasty (TKA) in elderly patients. MATERIAL AND METHODS: Ninety-eight patients with osteoarthritis who were 80 years of age or older and underwent concomitant cemented bilateral TKA were matched (on the basis of gender, surgeon, year of surgical treatment, age, and diagnosis) with 98 patients who underwent cemented unilateral TKA to compare the number and types of complications in these two groups. The groups did not differ in the number and type or severity of premorbid medical conditions, anesthetic risk, and type of anesthesia. RESULTS: One hundred nineteen postoperative complications occurred in 63 patients in the bilateral TKA group; in contrast, 72 complications occurred in 49 patients in the unilateral TKA group. The difference between the two groups in the total number of complications was significant. Specifically, significant differences between the two groups were noted in the occurrence of cardiovascular and neurologic complications. On paired analysis, congestive heart failure and acute delirium were found to be significantly more frequent in the bilateral TKA group than in the unilateral TKA group. We noted a trend toward an increased mortality rate in the bilateral group (four patients) versus the unilateral group (no deaths). CONCLUSION: Patients 80 years of age or older who undergo concomitant bilateral TKA are at increased risk for cardiovascular and neurologic complications during the postoperative period in comparison with matched patients who undergo unilateral TKA.

Aged↗

PubMed1996

Noninvasive doppler echocardiographic evaluation of left ventricular filling pressures in patients with cardiomyopathies: a simultaneous Doppler echocardiographic and cardiac catheterization study.

OBJECTIVES: The purpose of this study was to examine the relation of the mitral flow velocity curves to left ventricular filling pressures in patients with two different types of myocardial problems: hypertrophic cardiomyopathy and severe left ventricular systolic dysfunction. BACKGROUND: Previous studies have suggested that assessment of Doppler-derived mitral flow velocity curves can be used to predict left ventricular filling pressures in specific disease entities. However, it is unclear whether information derived from specific mitral flow velocity curves obtained from one disease entity can be valid in other disease states. METHODS: The study group consisted of 42 patients with left ventricular systolic dysfunction (group A) and 55 patients with hypertrophic cardiomyopathy (group B); both groups underwent simultaneous cardiac catheterization and were studied by Doppler echocardiography. High fidelity measures of left atrial and left ventricular pressures were obtained simultaneously with mitral flow velocity curves. RESULTS: There was a significant relation between the Doppler echocardiographic variables and mean left atrial pressure in group A patients. The left atrial pressure was directly related to the E/A ratio (r = 0.49, p = 0.004) and inversely related to the deceleration time (r = 0.73, p < 0.001). The sensitivity and specificity of the deceleration time, < 180 m/s, which indicated a mean left atrial pressure > or = 20 mm Hg, were both 100%. In group B patients, there was no significant relation between mean left atrial pressure and deceleration time. CONCLUSIONS: Doppler echocardiographic mitral flow velocity curves are useful in predicting and estimating left ventricular filling pressures in patients with left ventricular dysfunction. However, because of the complexity of the multiple interrelated factors that determine diastolic filling of the left ventricle, these flow velocity curves cannot be used in patients with other disease entities, such as hypertrophic cardiomyopathy. Future studies of different disease states are necessary to fully understand the role of Doppler echocardiography in the assessment of diastolic filling.

Adult↗

PubMed1996

Risk factors of invasive Candida and non-Candida fungal infections after liver transplantation.

Fungal infections are associated with a high mortality rate after liver transplantation. To describe risk factors for fungal infections, 405 consecutive liver transplant recipients were analyzed. Forty-five patients (11%) developed invasive fungal infection. Median posttransplantation time to the first episode was 60 days. Pathogens were Candida species (spp) (n=24, 53%), Cryptococcus neoformans (n=10, 22%), Aspergillus spp (n=6, 13%), Rhizopus spp (n=l), and others (n=4). Presentations of infection included disseminated (n=9), intra-abdominal (n=9), esophageal (n=9), lung (n=8), blood (n=6), and central nervous system infections (n=3), and sinusitis with esophagitis (n=1). Eighteen patients (40%) with invasive fungal infection died, and 13 (72%) of these deaths were attributable to fungi. Mortality in the nonfungal infection group was 12%. Univariate analysis identified separate risk factors for Candida (intra-abdominal bleeding), Aspergillus (fulminant hepatitis), and cryptococcal (symptomatic cytomegalovirus infection) infections. In both univariate and multivariate analyses, a high intratransplant transfusion requirement and posttransplant bacterial infection were identified as significant risk factors for all types of fungal infection. The risk factor analysis reported here suggests that different pathogenic processes lead to Candida and non-Candida infection in liver transplant recipients. Their identification should prompt specific prophylactic measures to reduce morbidity and mortality in this population.

Analysis of Variance↗

PubMed1996

Relevance and risk factors of enterococcal bacteremia following liver transplantation.

To analyze the clinical characteristics of and identify specific risk factors for enterococcal bacteremia following liver transplantation, we performed a study in 405 consecutive liver transplantation recipients prophylaxed with a selective bowel decontamination regimen. Seventy enterococcal bacteremias in 52 patients were identified. Enterococcus faecalis (50) outnumbered Enterococcus faecium isolates (18), and 49% of enterococcal bacteremias were polymicrobial. Biliary tree complications were present in 34% of enterococcal bacteremias. Of the 15 deaths (29%) among the patients with enterococcal bacteremia, 4 were directly associated with enterococcal bacteremia. In a multivariate analysis, Roux-en-Y choledochojejunostomy (P=0.005), a cytomegalovirus-seropositive donor (P=0.013), prolonged transplantation time (P=0.02), and biliary stricturing (P=0.016) were identified as significant risk factors. Other risk factors identified in a univariate analysis included primary sclerosing cholangitis (P=0.009) and symptomatic cytomegalovirus infection (P=0.008). Enterococcal bacteremia is a frequent infectious complication in liver transplantation recipients receiving selective bowel decontamination. Its association with cytomegalovirus and biliary tree abnormalities suggest specific areas for prophylactic intervention.

Anastomosis, Roux-en-Y↗

PubMed1996

Surgical aspects of patients with adenocarcinoma of the stomach operated on for cure.

BACKGROUND: A retrospective study was performed to evaluate our recent results of curative gastric resections for adenocarcinoma. METHODS: Between 1979 and 1988, 187 patients fulfilled study entry criteria. This group of patients composes 64% of all patients with tumors arising distal to the gastroesophageal junction. Tumors arising in the region of the gastroesophageal junction were excluded. Patients were classified according to the American Society of Anesthesiologists physical status classification ( > or = 3, 56%) and Eastern Cooperative Oncology Group performance status ( > or = 2, 44%). Histologic characteristics were re-reviewed. INTERVENTIONS: Subtotal and total gastrectomies were performed in 78% and 22% of the patients, respectively. Extended lymph node dissections were performed selectively (5%). Adjuvant chemotherapy and radiotherapy were employed in 3% and 2% of patients, respectively. RESULTS: Postoperative morbidity and mortality were 27% and 4%, respectively. Synchronous splenectomy (P = .06) and type of gastric resection (P = .06) showed a borderline association with postoperative complications, but did not affect postoperative mortality. With a median follow-up time of 47 months in all patients, and a median of 9 years in patients still alive, the 5- and 10-year overall survival rates (Kaplan-Meier method) were 48% and 32%, respectively. In univariate survival analysis, age, American Society of Anesthesiologists classification, stage, tumor diameter, serosal extension of tumor lymph node metastases, and type of resection showed prognostic significance. In the Cox multivariate analysis, however, only serosal extension of tumor (P < .001) and lymph node metastases (P = .02) were independent prognostic factors. CONCLUSIONS: Despite the older age and comorbid conditions of patients with gastric cancer, 5-year survival was achieved in half the patients by standard radical operations. Until appropriate controlled prospective studies are performed, total gastrectomy, splenectomy, and extended lymph node dissection should not be routinely adopted, given their unproven efficacy and potentially increased morbidity and mortality.

Adenocarcinoma↗

PubMed1996

Risk of recurrent biliary tract disease after cholecystectomy in patients with duodenal diverticula.

OBJECTIVE: To determine if the presence of duodenal diverticula predisposes to the development of common bile duct stones. DESIGN: Cohort study; median follow-up, 10.0 years (25th and 75th percentiles, 5.2 and 16.1 years, respectively). SETTING: Tertiary care center. PATIENTS: One hundred fifty-seven patients with radiologically diagnosed duodenal diverticula who had undergone cholecystectomy from 1950 through 1987 and were asymptomatic at the initiation of follow-up. MAIN OUTCOME MEASURES: All patients were followed up for evidence of recurrent biliary tract disease to the following end points: (1) evidence of choledocholithiasis demonstrated by radiologic surgical, or biochemical means and (2) clinical or biochemical evidence of biliary pancreatitis. RESULTS: Of the 157 patients in the study cohort, 13 patients were categorized as having had recurrent biliary tract disease. Using the Kaplan-Meier survivorship method, the cumulative probabilities of recurrent biliary tract disease in patients with radiologically diagnosed duodenal diverticula were 3.6% at 5 years (95% confidence interval, 0.5-6.9), 5.5% at 10 years (95% confidence interval, 1.5-9.4), and 10.2% at 15 years (95% confidence interval, 3.8-16.7). Age, common bile duct exploration and choledochotomy, and the presence of common bile duct dilatation were not found to be significantly associated with recurrence based on a univariate analysis of risk factors by means of the log-rank statistic. CONCLUSIONS: For patients with radiologically diagnosed, second-portion duodenal diverticula, the risk of developing recurrent bile duct stones after cholecystectomy is lower than has been suggested in previous studies. In the absence of concurrent choledocholithiasis, sphincterotomy or biliary bypass at the time of cholecystectomy seems unwarranted.

Adult↗

PubMed1996

Development of monoclonal gammopathy precedes the development of Epstein-Barr virus-induced posttransplant lymphoproliferative disorder.

Epstein-Barr virus (EBV)-induced posttransplant lymphoproliferative disorder (PTLD) develops in 3% to 10% of solid organ transplant recipients with a resultant mortality of up to 70%. Unfortunately, there is no current marker which identifies patients who will develop this disease. We therefore conducted a risk factor analysis of variables that might predict the development of PTLD. Specifically, since EBV may cause both PTLD and the development of monoclonal proteins (M protein), we sought to determine if the development of an M protein preceded and therefore might serve as a predictive marker of subsequent PTLD. Before and after liver transplantation, 201 patients were evaluated for the presence of urine and serum M proteins. Patients were followed to monitor the development of PTLD for a mean of 1,733 days. PTLD developed in seven patients (3.5%), three (43%) of whom died from disseminated PTLD. PTLD was classified as polymorphous in six patients and monomorphous in one patient. Fifty-seven patients (28%) developed an M protein after transplantation: five of seven patients (71%) with PTLD and 52/194 (27%) of patients without PTLD. Multivariate risk factor analysis for the development of an M protein after transplantation identified cytomegalovirus (CMV) donor seropositivity (P = 0.0002) and postoperative symptomatic CMV infection (P = 0.019) as risk factors. Whereas EBV serostatus of either the donor or recipient was not found to be a risk factor for the occurrence of either an M protein or PTLD, the development of a serum immunoglobulin M (IgM) M protein (P = 0.04) and of any urine M protein (P = 0.01) was identified by univariate analysis as being associated with the development of PTLD. Further studies are needed to determine the predictive value of M proteins as a marker for PTLD. Until such time, the development of serum or urine M protein should heighten the suspicion of developing PTLD.

Adolescent↗

PubMed1996

Curative reoperations for locally recurrent rectal cancer.

PURPOSE: Our aims were to determine the morbidity, survival and its influencing factors, and patterns of failure for patients who underwent further surgery with the hope of cure for locally recurrent rectal cancer. METHODS: Between January 1981 and December 1988, 224 patients with a preoperative diagnosis of recurrent rectal cancer underwent additional surgery at Mayo Medical Center in Rochester, Minnesota. Of these, 65 underwent further surgery with the hope of cure, i.e., no gross/microscopic residual disease at tumor margins after reoperation. Factors assessed included type of original operation, time interval between operation for primary tumor and initial operation for recurrence, symptom status, degree of fixation, types of reoperations for recurrence, and adjuvant therapy. RESULTS: None of the patients died within 30 days of reoperation. Seventeen complications requiring hospitalization and/or surgical procedure were observed in 14 patients. Extended operations (involving partial or complete removal of surrounding organs/structures) required more time to perform, a greater number of transfusions, and a longer hospital stay than more limited operations. Three-year, five-year, and median survival were 57, 34, and 44.7 months, respectively. Survival was greater after curative than after palliative resection (P < 0.001). Survival tended to be greater in females (P < 0.075) and in patients without pain (P < 0.065). Cumulative probability of local failure was 24, 41, and 47 percent at 1, 3, and 5 years, respectively. Cumulative risk of distant metastasis was 30, 51, and 62 percent at 1, 3, and 5 years, respectively. CONCLUSIONS: Our results indicate that complete excision of locally recurrent rectal cancer can provide a significant number of patients with long-term survival and can be accomplished safely in select patients.

Antimetabolites, Antineoplastic↗

PubMed1996

Surgical treatment of Graves' disease in patients younger than 18 years.

Eighty-two children and adolescents (18 males, 64 females; median age 14 years) surgically treated for Graves' disease at a single institution between 1979 and 1993 were retrospectively reviewed. Most of the patients (74%) coming to thyroidectomy had been treated medically for a period ranging from 2 to 80 (median 15) months. Bilateral subtotal thyroid resection was the most frequently performed procedure (86%). Postoperatively, no permanent recurrent laryngeal nerve palsy or permanent hypocalcemia occurred. Operative mortality was zero. With a median follow-up of 8.3 years, recurrent hyperthyroidism occurred in five patients (6%), one of whom required reoperation. Most children and adolescents with Graves' disease can be rendered euthyroid by nonsurgical treatment options. However, prolonged and ineffective medical treatment should be avoided in these patients who are in the formative years of their lives. Surgical treatment, when indicated and employed, offers young patients with Graves' disease a safe, rapid, definitive, cost-effective treatment with a high success rate.

Adolescent↗

PubMed1996

Effect of dual-chamber pacing on systolic and diastolic function in patients with hypertrophic cardiomyopathy. Acute Doppler echocardiographic and catheterization hemodynamic study.

OBJECTIVES: This study sought to evaluate prospectively the acute hemodynamic effect of dual-chamber pacing by using a combined hemodynamic approach of high fidelity pressure and Doppler velocity measurements. BACKGROUND: Dual-chamber pacing has been proposed recently as an alternative in the symptomatic treatment of patients with hypertrophic obstructive cardiomyopathy. Although early reports documented a decrease in left ventricular outflow tract gradient and symptomatic improvement, questions remain about the hemodynamic effects of dual-chamber pacing on systolic and diastolic function. METHODS: Twenty-nine patients with hypertrophic cardiomyopathy underwent a combined cardiac catheterization and Doppler echocardiographic study during normal sinus rhythm and P-synchronous pacing at various atrioventricular (AV) intervals. High fidelity pressure measurements of left ventricular inflow and left atrial pressures, ascending aortic pressure, thermodilution cardiac output and Doppler mitral flow velocity curves were obtained to evaluate both systolic and diastolic left ventricular function. RESULTS: During AV pacing at the shortest delay of 60 ms, there was a significant decrease in cardiac output (p < 0.05) and peak positive dP/dt (p < 0.05), an increase in mean left atrial pressure (p < 0.05) and a prolongation of tau, the time constant of relaxation (p < 0.05), compared with that during normal sinus rhythm. During pacing at the optimal AV delay (longest AV interval with pre-excitation), there was a similar trend, with deterioration in both systolic and diastolic function variables but of lesser magnitude than that during pacing at the shortest AV intervals. The deterioration in both systolic and diastolic function was present in 21 patients with and 8 without left ventricular outflow obstruction. There was a modest decrease in left ventricular outflow tract gradient from 73.3 +/- 45.0 (mean +/- SD) to 61.3 +/- 40.5 mm Hg (p = 0.03) during dual-chamber pacing at the optimal AV delay compared with that during normal sinus rhythm. CONCLUSIONS: The acute effect of pacing the right atrium and ventricle may be detrimental to both systolic and diastolic function of the left ventricle, particularly at the short AV intervals. Further studies of the long-term effects of dual-chamber pacing in carefully performed randomized studies are needed.

Blood Flow Velocity↗

PubMed1996

Clinical features of Graves' ophthalmopathy in an incidence cohort.

PURPOSE: To determine the clinical characteristics of an incidence cohort of patients with Graves' ophthalmopathy. METHODS: We reviewed the community medical records of 120 patients residing in Olmsted County, Minnesota, in whom Graves' ophthalmopathy was diagnosed between 1976 and 1990. RESULTS: Among 120 patients with Graves' ophthalmopathy, 108 (90%) patients had Graves' hyperthyroidism, one (1%) had primary hypothyroidism, four (3%) had Hashimoto's thyroiditis, and seven (6%) were euthyroid. At some point in their clinical course, eyelid retraction was present in 108 patients, whereas the approximate frequency of exophthalmos was 62% (73 patients); restrictive extraocular myopathy, 43% (51 patients); and optic nerve dysfunction, 6% (seven patients). Only six (5%) patients had eyelid retraction, exophthalmos, optic nerve dysfunction, extraocular muscle involvement, and hyperthyroidism. At the time of diagnosis of ophthalmopathy, upper eyelid retraction and eyelid lag were documented in 85 and 52 patients, respectively, and the most frequent ocular symptom was pain (36 patients, 30%). Diplopia was noted at the initial examination by 20 patients, lacrimation was present in 25 patients, 19 patients had photophobia, and nine patients had blurred vision. Decreased vision from optic neuropathy was present in less than 2% of eyes at the time of diagnosis. Thyroid dermopathy and acropachy accompanied Graves' ophthalmopathy in five patients (4%) and one (1%) patient, respectively. Myasthenia gravis occurred in only one patient. CONCLUSIONS: Eyelid retraction is the most common clinical sign of Graves' ophthalmopathy. The complete constellation of typical features (hyperthyroidism, eyelid retraction, exophthalmos, restrictive extraocular myopathy, and optic nerve dysfunction) occurs relatively infrequently.

Cohort Studies↗