PubMed Health⌕ Search

Biomedical subjects

Kenton J Zehr

Publications and source records attributed to Kenton J Zehr.

At least 19 recordsLinked to original sources
PubMed2006

Left atrial volume predicts the risk of atrial fibrillation after cardiac surgery: a prospective study.

OBJECTIVES: This study sought to identify preoperative predictors of postoperative atrial fibrillation (POAF) among patients undergoing cardiac surgery. BACKGROUND: Postoperative atrial fibrillation is frequent after cardiac surgery and is associated with increased morbidity, mortality, prolonged hospital stay, and increased costs. Left atrial volume (LAV), a marker of chronically elevated left ventricular filling pressure, is a predictor of atrial fibrillation (AF) in the nonsurgical setting. METHODS: A total of 205 patients (mean age 62 +/- 16 years; 35% women) undergoing cardiac surgery were prospectively enrolled. Clinical risk factors were obtained by detailed medical record review and patient interview. Preoperative transthoracic echocardiograms were performed for assessment of LAV, left ventricular ejection fraction, and diastolic function. Follow-up was complete. Detection of POAF was based on documentation of AF episodes by continuous telemetry throughout hospitalization. RESULTS: Postoperative atrial fibrillation occurred in 84 patients (41.4%) at a median of 1.8 days after cardiac surgery. The LAV was significantly larger in patients in whom AF developed (49 +/- 14 ml/m2 vs. 39 +/- 16 ml/m2, p = 0.0001). Patients with LAV >32 ml/m2 had an almost five-fold increased risk of POAF, independently of age and clinical risk factors (adjusted hazard ratio 4.84, 95% confidence interval 1.93 to 12.17, p = 0.001). Age and LAV were the only independent predictors of POAF. The area under the receiver-operator characteristics curve to predict POAF was 0.729 for LAV and 0.768 for the combination of LAV and age (both p < 0.0001). CONCLUSIONS: The LAV is a strong and independent predictor of POAF. Risk stratification using LAV and age enables clinicians to identify high-risk patients before cardiac surgery.

Adult↗
PubMed2006

Outcome of patients with low ejection fraction undergoing coronary artery bypass grafting: renal function and mortality after 3.8 years.

BACKGROUND: There are few data regarding medium-term outcome of coronary artery bypass grafting (CABG) in patients with severe left ventricular (LV) systolic dysfunction, particularly in the modern era, and even less assessing preoperative factors that might identify patients at highest risk. METHODS AND RESULTS: Three hundred seventy-nine consecutive patients with LV ejection fraction < or = 35%, who underwent isolated first CABG between 1995 and 1999 were studied. Potential preoperative and perioperative predictors of outcome were recorded and patients followed-up for a median of 3.8 years. The primary study end-point was all-cause mortality. The 30-day, 1-year, and 3-year survival rates were 94.5%, 88%, and 81%, respectively. The independent predictors of mortality were preoperative estimated glomerular filtration rate (hazard ratio [HR], 0.98; 95% confidence interval [CI], 0.97 to 0.99 per mL/min/1.73 m2; P<0.001) and age (HR, 1.03; 95% CI, 1.01 to 1.06 per year; P=0.005). CONCLUSIONS: Patients with significant LV systolic dysfunction undergoing isolated CABG using contemporary techniques have a good medium-term survival. Renal dysfunction is the strongest independent predictor of mortality.

Aged↗
PubMed2006

Right-sided Maze procedure for atrial tachyarrhythmias in congenital heart disease.

BACKGROUND: Congenital heart disease (CHD) that causes right atrial dilatation is commonly associated with atrial flutter and/or fibrillation (AFl/F). To reduce late recurrence of AFl/F in patients undergoing repair of CHD, we utilized a concomitant right-sided maze procedure. METHODS: From 1993 to 2003, 99 patients with CHD and associated AFl/F underwent a concomitant right-sided maze procedure at the time of CHD repair. Ages ranged from 9 to 72 years (median, 43 years). Atrial flutter and/or fibrillation was paroxysmal in 81 and chronic in 18; duration ranged from less than 1 month to 39.5 years (median, 2.9 years). Primary cardiac diagnoses were Ebstein anomaly (n = 47), other congenital tricuspid regurgitation (n = 19), univentricular heart (n = 11), isolated atrial septal defect (ASD, n = 8), tetralogy of Fallot (n = 8), and other (n = 6). RESULTS: Other concomitant procedures included tricuspid valve repair or replacement (n = 70), ASD closure (n = 39), and pulmonary valve procedures (n = 18). There were 6 early deaths. At hospital dismissal, 83 patients were free of AFl/F and 63 were in sinus rhythm. Follow-up in 87 of the 93 early survivors extended up to 8 years (mean, 2.7 years). There were 4 late deaths, all from noncardiac causes. Of the 83 known late survivors, 77 (93%) were free of AFl/F. Eighty-two of the 83 survivors were in New York Heart Association class I or II. CONCLUSIONS: In patients with AFl/F associated with CHD, a concomitant right-sided maze procedure at the time of intracardiac repair is effective in reducing late recurrent AFl/F. Most patients enjoy an excellent quality of life.

Adolescent↗
PubMed2006

Thoracic aorta false aneurysm: what surgical strategy should be recommended?

BACKGROUND: Thoracic aorta false aneurysms (TAFA) are a surgical challenge. The best technical approach remains uncertain. METHODS: Between 1981 and 2004, 57 patients underwent operation for TAFA (mean age 57 +/- 18 years; 43 [75%] were male). Symptoms included dyspnea 25 (44%), chest pain 22 (39%), and fever 18 (32%). Twelve (21%) were asymptomatic. Thirty-seven (65%) had undergone previous operation with a mean interval between operations of 80 +/- 90 months. Fifteen (26%) had a mycotic etiology. The TAFA involved the aortic root in 10 (18%), ascending aorta in 28 (49%), arch in 6 (11%), and descending aorta in 13 (32%). Twenty-one (37%) required femorofemoral cannulation and 28 (49%), circulatory arrest. Surgical techniques included graft replacement in 27 (47%), composite root in 10 (18%), patch repair in 10 (18%), and direct suture in 10 (18%). RESULTS: Operative mortality was 7% (4 patients). Four of 32 (13%) had massive hemorrhage during redo sternotomy, and all of these had planned extramediastinal cannulation (all survived). Follow-up was 100% for 349 patient-years. Actuarial survival was 77% +/- 6%, 63% +/- 8%, and freedom from recurrent TAFA was 87% +/- 5% and 83% +/- 7%, at 5 and 10 years, respectively. Univariate analysis identified TAFA greater than 55 mm, urgent operation, and NewYork Heart Association functional class III or IV as predictors of hemorrhage during redo sternotomy. Obesity and ejection fraction of 35% or less were predictors of operative death. CONCLUSIONS: Thoracic aorta false aneurysm symptoms may be minimal, and consequently a high degree of suspicion plus serial imaging is warranted. Extramediastinal cannulation, deep hypothermia, and circulatory arrest are required for large mediastinal TAFA. Despite serious risks, TAFA correction is possible with good long-term results.

Adult↗
PubMed2006

Left ventricular dysfunction in atrial fibrillation: restoration of sinus rhythm by the Cox-maze procedure significantly improves systolic function and functional status.

BACKGROUND: Atrial flutter or fibrillation with rapid, uncontrolled ventricular response may lead to left ventricular dysfunction, and conversion to sinus rhythm with control of heart rate can improve left ventricular ejection fraction. Little is known about the effects of the Cox-maze procedure on this form of tachycardia-induced cardiomyopathy. METHODS: Four hundred forty-three patients underwent the Cox-maze procedure from 1993 to 2002. Ninety-nine had atrial flutter or fibrillation without associated valvular or congenital heart disease, and 37 (37%) had decreased left ventricular function (ejection fraction < 0.35 in 11 [severe], ejection fraction 0.36 to 0.45 in 8 [moderate], and ejection fraction 0.46 to 0.55 in 18 [mild]). Ages of these 37 patients (34 male) ranged from 35 to 74 years (median, 55 years). RESULTS: Atrial flutter or fibrillation was present for 3 months to 19 years (median, 48 months) preoperatively, and 24 patients (65%) exhibited symptoms of heart failure. Preoperative ejection fraction ranged from 0.25 to 0.55 (median, 0.45). At last follow-up (median, 63 months), the Cox-maze procedure eliminated atrial flutter or fibrillation in all but 1 patient, and the greatest improvement was observed in patients with severe preoperative impairment (0.31 to 0.53; p = 0.01, preoperative versus follow-up), and patients with preoperative chronic atrial flutter or fibrillation (0.43 to 0.55; p < 0.05 preoperative versus follow-up). This improvement was observed immediately postoperatively and was sustained at last follow-up. Further, improvement in left ventricular function correlated with enhancement of functional status. CONCLUSIONS: In some patients, atrial flutter or fibrillation may be the cause rather than the consequence of left ventricular dysfunction. Importantly, systolic function and functional status can be significantly improved with the restoration of sinus rhythm by the Cox-maze procedure.

Adult↗
PubMed2006

The effect of adjuvant perfusion techniques on the incidence of paraplegia after repair of traumatic thoracic aortic transections.

OBJECTIVE: To analyze the effect of adjuvant perfusion techniques of the distal aorta on the outcome of traumatic thoracic aortic transections. PATIENTS AND METHODS: From 1973 to 2004, 72 patients (mean age, 39 years) with thoracic aortic transections arrived alive at the emergency department. Nineteen patients arrived in extremis and underwent emergency operations, 42 patients were stable and underwent diagnostic evaluation before surgery (4 patients experienced aortic rupture during evaluation), and 11 patients presented more than 24 hours after the accident. Sixteen patients died before aortic repair could be performed. Operative repair was possible in 53 patients (46 stable and 7 in extremis). Interposition graft was performed in 47 patients, and primary repair was performed in 6 patients. Morbidity, mortality, and paraplegia rate were analyzed. RESULTS: Patients in extremis had a mortality rate of 84% (16 of 19), stable patients had a mortality rate of 11% (4 of 38), patients who experienced rupture during evaluation had a mortality rate of 100% (4 of 4), and patients who underwent delayed operation had a mortality rate of 0% (0 of 11). The paraplegia rate with and without adjuvant distal aortic perfusion techniques was 2% (1 of 41 patients) and 33% (4 of 12 patients), respectively (P=.007). Mortality and paraplegia rates were 4% and 4% for partial bypass (n=24), 42% and 33% for the clamp and sew technique (n=12), 0% and 0% for Gott shunt (n=10), and 29% and 0% for full cardiopulmonary bypass (n=7), respectively. CONCLUSIONS: Although thoracic aortic transections remain a highly lethal injury, hemodynamically stable patients have a low operative mortality. Spinal cord injury is decreased by the use of adjuvant perfusion techniques that maintain distal aortic perfusion during cross-clamping of the aorta.

Adult↗
PubMed2006

Surgical treatment of the cardiac manifestations of relapsing polychondritis: overview of 33 patients identified through literature review and the Mayo Clinic records.

OBJECTIVES: To analyze the cardiac findings that necessitate surgery in patients with relapsing polychondritis (RP) and to compare our results to cases in the literature. MATERIAL AND METHODS: A systematic overview of the literature was completed with the addition of cases of RP from the Mayo patient population that necessitated cardiac surgery. RESULTS: Thirty-three patients were identified (25 from the literature and 8 from the Mayo patient population). Nine patients (27%) were female, 22 (67%) were male, and sex was not stated for 2 patients (6%). The patient age ranged from 17 to 69 years (mean +/- SD, 42.5 +/- 15.7 years). At operation, 30 patients (91%) had aortic regurgitation, 21 (64%) had aortic root disease, and 13 (39%) had mitral regurgitation. The most common surgical procedure performed was aortic valve replacement in 12 patients (36%). The most common complications were death in 12 patients (36%) and prosthetic valve dehiscence in 4 patients (12%). CONCLUSIONS: Cardiac involvement is more prominent in the male population and requires more invasive procedures. Aortic valve replacement with composite graft replacement of the ascending aorta along with coronary artery ostial reimplantation should be considered in these patients. Postsurgical valvular complications include prosthetic dehiscence, paravalvular leakage, mediastinitis, and heart failure, and these complications are associated with postoperative corticosteroid therapy. Initiation of second-line immunosuppressive therapy should be substituted for corticosteroids after cardiac surgery.

Adolescent↗
PubMed2006

A systematic overview of anomalous coronary anatomy and an examination of the association with sudden cardiac death.

Coronary artery anomalies are a frequently neglected topic in cardiology. However, they are an important cause of cardiac ischemia and sudden death. Anomalous pulmonary artery and anomalous aortic origins of the coronaries are 2 major types of coronary artery anomalies. This article will examine the occurrence of these anomalies in the absence of associated congenital defects. A review of the literature reveals that the anomaly most commonly associated with sudden death is a left main coronary artery arising from the right aortic sinus of Valsalva with an interarterial course. The increased risk of sudden death with this anomaly has been associated with any of 4 high-risk features: slit-like ostium, acute-angle take-off, intramural aortic segment, and interarterial course.

Coronary Vessel Anomalies↗
PubMed2005

Aortic root dilatation may alter the dimensions of the valve leaflets.

OBJECTIVE: Valve-sparing surgery can be used in patients with dilated aortic roots and aortic insufficiency (AI) but has not become a common practice, in part because the spared valve may be incompetent. Our goal was to study how the dimensions of the aortic root and leaflets have changed in such patients. METHODS: Fourteen patients with dilated aortic root and AI were examined by transesophageal echocardiography. The annulus diameter, sinotubular junction (STJ) diameter, sinus height, leaflet free-edge length, and leaflet height were measured. Correlations among these dimensions and with the AI grades were explored. Measurements were also made in 19 normal human aortic valves from silicone molds. RESULTS: There was no evident change in the average diameter of the annulus between the normal valves and those in the dilated aortic roots. The STJ diameter was obviously increased in the dilated aortic roots; the aortic sinuses also appeared to be taller and the leaflets larger than normal. The leaflet free-edge length, the leaflet height, and the sinus height were found to increase with the dilated STJ diameter. The degree of AI was not found to correlate well with any of the dimensions measured. CONCLUSIONS: The dimensions of the leaflets may change parallel to aortic root dilatation with AI. Therefore, during valve sparing, it may be necessary to correct both the dilatation of the root and the leaflet free-edge length to achieve a competent valve.

Adult↗
PubMed2005

Left atrial appendage aneurysm.

Aneurysms of the left atrial appendage are exceedingly rare. Patients most commonly present with atrial tachyarrhythmias and thromboembolism. Resection of the aneurysm is usually curative. We present a case report of a 60-year-old female with a long-standing history of atrial arrhythmias found to have a large left atrial appendage aneurysm with additional bi-atrial enlargement and a family history of atrial arrhythmias. The patient was successfully treated with resection of the aneurysm and a Cox-Maze III procedure.

Arrhythmias, Cardiac↗
PubMed2005

Idiopathic pulmonary artery aneurysm.

A case of idiopathic pulmonary artery aneurysm is presented along with a review of our experience of this rare condition. These entities may have an association with cystic medial degeneration of the arterial wall and are subject to the same complications as aortic aneurysms.

Aneurysm↗
PubMed2005

Surgical treatment of ascending aortic aneurysms in patients with giant cell aortitis.

BACKGROUND: Giant cell aortitis is a rare cause of ascending aortic aneurysm disease despite giant cell arteritis being a common cause of vasculitis. We evaluated an 8-year experience with surgical repair with regard to preoperative variables, extent of disease, required surgical procedures, and the propensity to develop additional great vessel aneurysms. METHODS: Thirty-seven patients (29 female, 8 male; aged 69.6 +/- 9.5 years) were operated on from 1995 to 2002. Ten (27%) patients had a history of steroid treatment for temporal arteritis or polymyalgia rheumatica 8.9 +/- 3.9 years before. Nineteen (51%) patients had +3 or +4 aortic regurgitation. Maximal aneurysm size was 6.1 +/- 0.8 cm. Thirty (81%) patients underwent polyethylene terephthalate fiber (Dacron) tube graft replacement of the ascending aorta, 4 (11%) had a modified Bentall procedure, 2 (5%) had a valve-sparing aortic root reconstruction, and 1 (3%) had aortorrhaphy. Twenty-two (59%) patients required 22 +/- 9 minutes of hypothermic circulatory arrest for hemiarch or complete aortic arch replacement. Twenty-six (70%) patients had concomitant cardiac procedures. RESULTS: There was no early mortality. Morbidity was reexploration for bleeding in 3 (8%) patients, stroke in 3 (8%), left vocal cord paralysis in 2 (5%), renal failure in 2 (5%), and gastrointestinal bleeding in 1 (3%). Mean follow-up was 2.8 +/- 2.3 years. Four-year actuarial survival was 74% (95% confidence interval, 57% to 94%). Other descending or abdominal aortic or great vessel aneurysms occurred in 17 (46%) patients. Four patients had prior aneurysm surgery, 8 are monitored with aneurysms, and 5 underwent repair of an aneurysm in the follow-up period. Of 8 late deaths, 3 were caused by complications of a descending thoracic aneurysm. No patient required replacement of a native aortic valve that was preserved during the initial operative procedure. CONCLUSIONS: Ascending aortic aneurysms caused by giant cell aortitis can involve the aorta from the aortic root through the aortic arch, thus requiring a tailored operative approach. The aortic valve tissue is spared from the pathologic process. Other aneurysms of the aorta and great vessels occur in nearly half of patients. Frequent surveillance of the remaining aorta is mandatory.

Aged↗
PubMed2005

Surgical treatment of cardiac papillary fibroelastoma: a single center experience with eighty-eight patients.

BACKGROUND: Cardiac papillary fibroelastoma is a rare benign tumor that can cause thromboembolism. We have found no large surgical series describing its treatment and outcome. METHODS: A retrospective review of all patients treated surgically for this tumor from 1985 to 2002. RESULTS: There were 88 patients with a mean age of 62 +/- 16 years. Sixty-two (71%) were male. Cardiac papillary fibroelastoma was a primary indication for surgery in 47 (group 1, 53%) and an incidental finding in 41 (group 2, 47%). The common clinical symptoms were neurologic (group 1) and cardiac (group 2). Cardiac valves were predominantly involved (77%); the aortic valve was the most affected (52%). Other common sites were the left ventricular outflow tract (18%) and anterior mitral leaflet (11%). All heart valves were involved in one patient. Seventy-three patients (83%) had shave excision and 8 (9%) excision with valve repair. Of 5 (6%) valve replacements, 2 were for concurrent degenerative valve disease. Concomitant procedures included repair or replacement of another valve (32%), CABG (28%), and septal myectomy (19%). Surgical mortality occurred in 1 patient (2.1%) in group 1 who had concomitant lung resection for bronchiolitis obliterans. There was no tumor recurrence, and no tumor-related late morbidity or mortality at a mean follow-up of 3 years. CONCLUSIONS: Cardiac papillary fibroelastoma has a propensity to affect the anatomically contiguous structures of the aortic valve, left ventricular outflow tract, and anterior mitral leaflet. Surgical treatment by simple shave excision is low risk and can achieve good results.

Adult↗
PubMed2005

Operative risk of reoperative aortic valve replacement.

OBJECTIVE: The contemporary risk of reoperative aortic valve replacement is ill-defined. We therefore compared the recent early results of reoperative and primary aortic valve replacement in our institution. METHODS: Between January 1993 and January 2001, a total of 162 patients underwent reoperative aortic valve replacement with or without coronary artery bypass grafting, and 2290 underwent primary aortic valve replacement with or without coronary artery bypass grafting. The reoperative and primary groups were similar with regard to gender (37% female in both), preoperative New York Heart Association functional class (2.8 +/- 1 vs 2.8 +/- 1), and ejection fraction (58% +/- 15% vs 57% +/- 15%). Patients undergoing reoperative aortic valve replacement were younger than those undergoing primary aortic valve replacement (64 +/- 15 years vs 70 +/- 13 years, P < .001). Previous prostheses were xenografts in 77 patients (48%), homografts and autografts in 25 (15%), and mechanical prostheses in 60 (37%). Mean time to reoperation was 9.7 +/- 6.8 years. RESULTS: Early mortality for reoperative aortic valve replacement (8/162, 5%) was not statistically different from that for primary aortic valve replacement (71/2290, 3%, P = .20). Endocarditis was more common in the reoperative group (22% vs 3%, P < .001); when endocarditis was excluded from the analysis, early mortality was 3% in both groups. Multivariate predictors for early mortality were prosthetic valve endocarditis ( P < .001, odds ratio 9.8), advanced preoperative functional class ( P < .001, odds ratio 2.0), peripheral vascular disease ( P = .008, odds ratio 2.0), preserved left ventricular ejection fraction ( P = .004, odds ratio 0.98), and male gender ( P = .009, odds ratio 0.49). After adjustment for these factors, there was no difference in early mortality between the groups ( P = .095). CONCLUSION: The risk of reoperative aortic valve replacement is similar to that for primary aortic valve replacement. These data support the expanded use of bioprosthetic valves in younger patients.

Age Factors↗
PubMed2005

Aortic root replacement with a novel decellularized cryopreserved aortic homograft: postoperative immunoreactivity and early results.

OBJECTIVE: Novel antigen-reduction SynerGraft technology (CryoLife Inc, Kennesaw, Ga) reduces the cellular components of a cadaver homograft with an enzymatic and washing process, leaving the extracellular matrix intact. We report the immunoreactivity (positive panel reactive antibody assay) and early operative results of the CryoLife SynerGraft aortic valve conduit homograft. METHODS: Twenty-two patients (age 53 +/- 14 years, range 31-80 years) from April 2002 to July 2003 underwent aortic root replacement with a CryoLife SynerGraft aortic valve conduit homograft (CryoLife Inc, Kennesaw, Ga) for congenital or acquired aortic valve disease, aortic aneurysm with aortic valve disease, or native or prosthetic aortic valve endocarditis. Baseline percentage positive panel reactive antibody results were negative (<10%) for all and were assessed at 1 month, 3 months, and 1-year. Homograft function was evaluated by echocardiography. RESULTS: Early mortality was 0%. Two late deaths at 1 postoperative year were unrelated to homograft function. At 1 postoperative month, panel reactive antibody results were negative in 20 patients (91%). At 3 months, 19 of 22 patients (86%) had negative results, including 1 with previous positive results. At 1 year, 19 of 20 patients (95%) had negative results, including 2 of the 3 with previous positive results. The mean aortic valve gradients were 12 +/- 8 mm Hg (n = 21) at discharge and 11 +/- 7 mm Hg (n = 18) at 1 year. At a mean follow-up of 30.3 +/- 5.2 months, the mean gradient was 8.8 +/- 6.3 mm Hg. CONCLUSION: The SynerGraft decellularization technology successfully removed antigens from an aortic valve homograft conduit. Aortic root reconstruction with the CryoLife SynerGraft aortic valve homograft resulted in low transvalvular gradients, similar to those seen with standard cryopreserved homografts. These early results suggest an advancement in homograft technology. The low panel reactive antibody response may enhance durability by eliminating immune complex-mediated reaction against the homograft. The lack of allosensitization in patients who may require organ transplantation in the future is an added benefit.

Adult↗
PubMed2005

Biventricular assist device placement and immunosuppression as therapy for necrotizing eosinophilic myocarditis.

BACKGROUND: A previously healthy 47-year-old woman presented reporting nausea, anorexia and light-headedness of 2 weeks' duration, and three episodes of syncope. She also had pleuritic chest pain and rapidly declining cardiac function. The only reported medical history was urinary tract infection and an ankle fracture sustained 5 months before presentation. She was receiving no medication other than estrogen patches for menopause and did not smoke or use illicit drugs. INVESTIGATIONS: Electrocardiography, chest radiography, echocardiography, measurement of creatinine phosphokinase and troponin T, coronary angiography and endomyocardial biopsy. DIAGNOSIS: Necrotizing eosinophilic myocarditis. MANAGEMENT: Biventricular assist device implantation, methylprednisolone, prednisolone and mycophenolate mofetil.

Coronary Angiography↗