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Shimon A Reisner

Publications and source records attributed to Shimon A Reisner.

18 recordsLinked to original sources
PubMed2006

Left ventricular filling hemodynamics in patients with pulmonary edema and preserved versus reduced left ventricular ejection fraction: a prospective Doppler echocardiographic study.

BACKGROUND: Objective evidence of elevated left ventricular (LV) filling pressures is infrequently demonstrated in clinical practice in patients with heart failure (HF) and preserved LV ejection fraction (LVEF) and the clinical diagnosis of HF is commonly questionable in these patients. The objective of this study was to examine whether elevated LV filling pressures can be demonstrated noninvasively in consecutive patients with HF and preserved (vs reduced) LVEF. METHODS: Echocardiography was performed in 141 patients hospitalized with acute pulmonary edema (within 3 days of admission in 83.6%). LV filling was assessed in 116 patients without significant valve disease (median age 76 years; 51.7% men) and LV filling pressures were estimated based on mitral and pulmonary venous flow patterns and mitral annular diastolic velocities. RESULTS: LVEF was preserved (> or =45%) in 49 patients (42.2%) and reduced (<45%) in 67 patients (57.8%). In patients with in sinus rhythm, normal LV filling pattern and abnormal relaxation, pseudonormal, and restrictive LV filling patterns (the latter two patterns associated with elevated LV filling pressures) were evident in 8, 1, 11, and 9 patients with preserved LVEF, versus 5, 11, 15, and 23 patients with reduced LVEF, respectively (P = .01) (LV filling pattern was nonconclusive in 12 patients). In patients with atrial arrhythmias, elevated LV filling pressures were evident in 4 of 14 patients with preserved LVEF and 3 of 4 patients with reduced LVEF. Overall, elevated LV filling pressures were demonstrable in 24 patients with preserved LVEF (49.0%) and in 41 patients with reduced LVEF (68.3%) (P = .26). CONCLUSIONS: Elevated LV filling pressures are frequently evident by Doppler echocardiography in patients with HF and preserved or reduced LVEF. Thus, Doppler echocardiography can provide objective noninvasive evidence of abnormal LV filling in a large proportion of patients with HF and preserved LVEF.

Aged↗
PubMed2006

Pulmonary hypertension in chronic dialysis patients with arteriovenous fistula: pathogenesis and therapeutic prospective.

PURPOSE OF REVIEW: End-stage renal disease patients receiving chronic haemodialysis via arteriovenous access often develop various cardiovascular complications, including vascular calcification, cardiac-vascular calcification and atherosclerotic coronary disease. This review describes recently published studies that demonstrate a high incidence of pulmonary hypertension among patients with end-stage renal disease receiving long-term haemodialysis via a surgical arteriovenous fistula. Both end-stage renal disease and long-term haemodialysis via arteriovenous fistula may be involved in the pathogenesis of pulmonary hypertension by affecting pulmonary vascular resistance and cardiac output. RECENT FINDINGS: Morbidity and mortality from cardiovascular disease are greatly increased in patients on maintenance haemodialysis therapy. Using Doppler echocardiography, we found a significant increase in cardiac output in 40% of chronic haemodialysis patients, probably related to the large arteriovenous access or altered vascular resistance as a result of the local vascular tone and function expressed by the imbalance between vasodilators such as nitric oxide, and vasoconstrictors such as endothelin-1. SUMMARY: We propose different potential mechanisms as explanations for the development of pulmonary hypertension. Hormonal and metabolic derangement associated with end-stage renal disease might lead to pulmonary arterial vasoconstriction and an increase in pulmonary vascular resistance. Pulmonary arterial pressure may be further increased by high cardiac output resulting from the arteriole-venous access itself, worsened by commonly occurring anaemia and fluid overload.

Adult↗
PubMed2005

Comparison of multidetector computed tomography versus echocardiography for assessing regional left ventricular function.

Multidetector computed tomography (MDCT) of the heart is a rapidly developing technique mainly used to evaluate the coronary arteries. However, it is also capable of evaluating ventricular function. It compares well with magnetic resonance imaging in calculating volumes and ejection fractions, but little has been reported on its ability to assess left ventricular (LV) segmental wall motion (LVSWM). This study compared semiquantitative LVSWM scoring by MDCT with echocardiography as the gold standard. Thirty-nine patients underwent MDCT angiography on a 16-slice scanner. Short- and long-axis LV slices were created at different phases of the cardiac cycle and visually evaluated using cine mode. Echocardiography was performed <48 hours after MDCT for 21 patients after acute myocardial infarctions and <1 month after MDCT for 18 patients without acute myocardial infarctions. Two blinded observers scored the MDCT and echocardiographic examinations according to the 16-segment model, scoring each segment from 1 (normal) to 3 (akinetic). Segmental dysfunction was found in 27 patients by echocardiography and in 24 by MDCT. An identical score was given by the 2 methods in 502 of 616 assessable segments (82%). Using a binary analysis (normal or abnormal), there was 89% agreement (546 of 616 segments). MDCT had a sensitivity of 66% (103 of 155 segments) and a specificity of 96% (443 of 461 segments) compared with echocardiography as the gold standard. Most disagreements occurred in the right coronary artery segments. In conclusion, MDCT can be used to evaluate LVSWM, showing good agreement with echocardiography, except for the right coronary artery segments.

Adult↗
PubMed2005

The pathogenesis of pulmonary hypertension in haemodialysis patients via arterio-venous access.

BACKGROUND: We recently have shown a high incidence of unexplained pulmonary hypertension (PHT) in end-stage renal disease (ESRD) patients on chronic haemodialysis (HD) therapy via arterio-venous (A-V) access. This study evaluated the possibility that PHT in these patients is triggered or aggravated by chronic HD via surgical A-V access, and the role of endothelin-1 (ET-1) and nitric oxide (NO) in this syndrome. METHODS: Forty-two HD patients underwent clinical evaluation. Pulmonary artery pressure (PAP) was evaluated using Doppler echocardiography. Levels of ET-1 and NO metabolites in plasma were determined before and after the HD procedure and were compared between subgroups of patients with and without PHT. RESULTS: Out of 42 HD patients studied, 20 patients (48%) had PHT (PAP = 46+/-2; range 36-82 mmHg) while the rest had a normal PAP (29+/-1 mmHg) (P<0.0001). HD patients with PHT had higher cardiac output compared with those with normal PAP (6.0+/-1.2 vs 5.2+/-0.9 l/min, P<0.034). HD patients, with or without PHT, had elevated plasma ET-1 levels compared with controls (1.6+/-0.7 and 2.4+/-0.8 fmol/ml vs 1.0+/-0.2, P<0.05) that remained unchanged after the HD procedure. HD patients without PHT and control subjects showed similar basal plasma levels of NO2 + NO3 (24.2+/-5.2 vs 19.7+/-3.1 microM, P>0.05) that was significantly higher compared with HD patients with PHT (14.3+/-2.3 microM, P<0.05). HD therapy caused a significant increase in plasma NO metabolites that was greater in patients without PHT (from 24.2+/-5.2 to 77.1+/-9.6 microM, P<0.0001, and from 14.3+/-2.3 to 39.9+/-11.4 microM, P<0.0074, respectively). Significant declines in PAP (from 49.8+/-2.8 to 38.6+/-2.2 mmHg, P<0.004) and cardiac output (CO) (from 7.6+/-0.6 to 6.1+/-0.3 l/min, P<0.03) were found in 11 HD patients with PHT that underwent successful transplantation. Similarly, temporary closure of the A-V access by a sphygmomanometer in eight patients with PHT resulted in a transient decrease in CO (from 6.4+/-0.6 to 5.3+/- 0.5 l/min, P = 0.18) and systolic PAP (from 47.2+/-3.8 to 34.6+/-2.8 mmHg, P<0.028). CONCLUSIONS: This study demonstrates a high prevalence of PHT among patients with ESRD on chronic HD via a surgical A-V fistula. In view of the vasodilatory and antimitogenic properties of NO, it is possible that the attenuated basal and HD-induced NO production in patients with PHT contributes to the increased pulmonary vascular tone. Furthermore, the partial restoration of normal PAP and CO in HD patients that underwent either temporal A-V shunt closure or successful transplantation indicates that excessive pulmonary blood flow is involved in the pathogenesis of the disease.

Adult↗
PubMed2005

Intermittent coronary sinus occlusion complicating coronary sinus cannulation during coronary artery bypass operation.

Coronary sinus (CS) thrombosis is a rare event, usually complicating invasive procedures that cause trauma to the CS. Based on anecdotal case reports, this pathology is frequently associated with serious complications and is commonly fatal. We describe a case of intermittent CS thrombosis resulting from CS cannulation during coronary artery bypass grafting operation. This complication was further complicated by myocardial infarction, left ventricular free wall rupture, and pseudoaneurysm formation. The characteristic echocardiographic findings and a review of the literature on this rare complication are presented.

Aged↗
PubMed2005

Haptoglobin polymorphism predicts 30-day mortality and heart failure in patients with diabetes and acute myocardial infarction.

Patients with diabetes presenting with acute myocardial infarction (AMI) have an increased rate of death and heart failure. Patients with diabetes homozygous for the haptoglobin (Hp) 1 allele (Hp 1-1) develop fewer vascular complications. We tested the hypothesis that Hp type is related to the outcome of patients with diabetes presenting with AMI. We prospectively assessed the relationship between Hp type and 30-day mortality and heart failure in 1,437 patients with AMI (506 with diabetes). Multivariate logistic regression identified a significant interaction between Hp type and diabetes status on these outcome measures. Hp type was not related to outcome among patients without diabetes. In contrast, Hp 1-1 was associated with a strong protective effect with regard to the primary end point of death (OR 0.14, P = 0.015) and for death and heart failure (OR 0.35; 95% CI 0.15-0.86, P = 0.018) among patients with diabetes. Finally, among patients with diabetes, Hp 1-1 was associated with smaller infarct size. This study demonstrates that in patients with diabetes and AMI, the Hp type is an important determinant of clinical outcome and infarct size.

Diabetes Mellitus↗
PubMed2004

Global longitudinal strain: a novel index of left ventricular systolic function.

BACKGROUND: Echocardiographic estimation of global left ventricular (LV) function is subjective and time consuming. Our aim was to develop a novel approach for assessment of global LV function from 2-dimensional echocardiographic images METHODS: Novel computer software for tissue tracking was developed and applied as follows: digital loops were acquired from apical 2-, 3-, and 4-chamber views and a line was loosely traced along the LV endocardium at the frame wherein it was best defined. Around this line, the software selected natural acoustic markers moving with the tissue. Automatic frame-by-frame tracking of these markers during the heart cycle yielded a measure of contractility along the selected region of interest. Global longitudinal strain (GLS) and GLS rate (GLSR) were calculated for the entire U-shaped length of LV myocardium (basal, mid, and apical segments of 2 opposite walls in each view). To test this software, computer-derived GLS and GLSR were analyzed by a nonechocardiographer, blinded to the echocardiographic interpretation, in 27 consecutive patients after myocardial infarction (MI) (age 64.4 +/- 12.9 years; 19 men; mean wall-motion score index of 1.79 +/- 0.44) and compared with those obtained in 12 consecutive control patients (age 59.0 +/- 9.7 years; 8 women), with a normal echocardiographic study. RESULTS: GLS and GLSR, averaged from the 3 apical views, differed significantly in patients post-MI compared with control patients (GLS -14.7 +/- 5.1% vs -24.1 +/- 2.9% and GLSR -0.57 +/- 0.21/s vs -1.02 +/- 0.09/s for patients post-MI vs control patients, respectively; both P <.0001). There was a good linear correlation between the wall-motion score index and the GLS and GLSR (R = 0.68 and R = 0.67, respectively; both P <.0001). A cut-off value for GLS of -21% had 92% sensitivity and 89% specificity and a cut-off value for GLSR -0.9/s had 92% sensitivity and 96% specificity for the detection of patients post-MI. CONCLUSIONS: GLS and GLSR are novel indices for assessment of global LV function from 2-dimensional echocardiographic images. Early validation studies with the method are suggestive of high sensitivity and specificity in the detection of LV systolic dysfunction in patients post-MI.

Adult↗
PubMed2004

Pulmonary calcification in hemodialysis patients: correlation with pulmonary artery pressure values.

BACKGROUND: End-stage renal disease (ESRD) patients receiving chronic hemodialysis (HD) via an arteriovenous (A-V) access often develop unexplained pulmonary hypertension (PHT). This study evaluated the role of pulmonary calcification (PC) in this phenomenon. METHODS: The clinical manifestations, systolic pulmonary artery pressure (PAP) values measured by Doppler echocardiography and the presence and the extent of PC expressed by lung uptake of 99mTc-MDP bone scintigraphy, were studied in 49 patients with ESRD receiving chronic HD therapy via A-V access. The correlation between PC and PHT was investigated. RESULTS: There were 36 men and 13 women with a mean age of 61.7 +/- 13.2 years receiving HD therapy for 38.2 +/- 43.7 months. Twenty (40.8%) patients had PC expressed by increased lung uptake of 99mTc- MDP and 28 (57.1%) patients had PHT with a mean systolic PAP of 46 +/- 11 mm Hg. No correlation was found between PC and PHT. CONCLUSION: The data suggest that PC expressed by lung uptake of 99mTc-MDP has no role in the pathogenesis of PHT among ESRD patients undergoing HD therapy via A-V access.

Adult↗
PubMed2004

Unexplained severe pulmonary hypertension in the elderly: report on 14 patients.

BACKGROUND: Unexplained pulmonary hypertension is assumed to occur mainly in young adults. OBJECTIVE: To describe the features of the disease in older patients and compare them to those in PHT patients of all ages. METHODS: We conducted a retrospective evaluation of the files of patients over 65 years of age in whom UPHT was diagnosed between 1987 and 1999 at two PHT centers serving a population of 4 million. Patients were followed for survival until March 2003. Clinical variables of the study patients were compared with those in PHT patients of all ages. RESULTS: The study group included 14 patients, 10 females and four males, with a mean age of 70.5 +/- 6.7 years. The calculated mean annual incidence of UPHT for the study population was one new case per year per million persons. Seven patients (50%) had systemic hypertension. The mean interval from onset of symptoms to diagnosis was 8.3 months. At diagnosis, 64% of patients had functional capacity of III-IV according to the New York Heart Association classification, and 43% had right heart failure. Mean systolic pulmonary artery pressure was 80 +/- 21 mmHg, peripheral vascular resistance 11.7 +/- 7 mmHg/L/min, cardiac index 2.16 +/- 0.81, and mean right atrial pressure 10.5 +/- 5.9 mmHg. Median survival time was 43 months; survival rates for 1 year, 3 years and 5 years were 92.6%, 50% and 40%, respectively. Compared to data from the U.S. National Institute of Health Registry, UPHT in older patients is more common in females, but the incidence as well as clinical, hemodynamic and survival parameters are similar to those in PHT patients at any age. CONCLUSIONS: UPHT occurs in the elderly more frequently than previously thought, with similar features in PHT patients of all ages. The coexistence of systemic and pulmonary hypertension warrants further investigation.

Aged↗
PubMed2003

Admission C-reactive protein levels and 30-day mortality in patients with acute myocardial infarction.

BACKGROUND: Elevated C-reactive protein levels are associated with an increased risk of subsequent cardiovascular events in patients with unstable angina. However, limited information is available concerning the value of C-reactive protein levels in patients with acute myocardial infarction. METHODS: We prospectively studied 448 consecutive patients (mean [+/- SD] age, 60 +/- 12 years) with acute myocardial infarction. Serum C-reactive protein levels were measured within 12 to 24 hours of symptom onset, and divided into tertiles. Infarct size was determined by echocardiographic examination that was performed on day 2 or 3. Patients were followed for 30 days for mortality and subsequent cardiac events. RESULTS: At 30 days, 4 deaths (3%) occurred in patients in the lowest C-reactive protein tertile, 15 (10%) in patients in the middle tertile (P = 0.02 vs. the lowest tertile), and 33 (22%) in patients in the highest tertile (P <0.001 vs. the lowest tertile). In a multivariate analysis, C-reactive protein in the upper tertile was associated with 30-day mortality (relative risk = 3.0; 95% confidence interval [CI]: 1.3 to 7.2; P = 0.01) and the development of heart failure (odds ratio = 2.6; 95% CI: 1.5 to 4.6; P = 0.0006). C-reactive protein levels were not associated with the development of postinfarction angina, recurrent myocardial infarction, or the need for revascularization. CONCLUSION: Plasma C-reactive protein level obtained within 12 to 24 hours of symptom onset is an independent marker of 30-day mortality and the development of heart failure in patients with acute myocardial infarction. These findings suggest that C-reactive protein levels may be related to inflammatory processes associated with infarct expansion and postinfarction ventricular remodeling.

Age Factors↗
PubMed2003

Pulmonary hypertension in patients with end-stage renal disease.

BACKGROUND: The aims of this study were to evaluate the incidence of unexplained pulmonary hypertension (PH) among patients with end-stage renal disease (ESRD) and to suggest possible etiologic factors. METHODS: The incidence of PH was prospectively estimated by Doppler echocardiography in 58 patients with ESRD receiving long-term hemodialysis via arteriovenous access, and in control groups of 5 patients receiving peritoneal dialysis (PD) and 12 predialysis patients without a known other cause to suggest the presence of PH. Clinical variables were compared between patients with and without PH receiving hemodialysis. Changes in pulmonary artery pressure (PAP) values before and after onset of hemodialysis via arteriovenous access, arteriovenous access compression, and successful kidney transplantation were recorded. RESULTS: PH > 35 mm Hg was found in 39.7% of patients receiving hemodialysis (mean +/- SD, 44 +/- 7 mm Hg; range, 37 to 65 mm Hg), in none of the patients receiving PD, and in 1 of 12 predialysis patients. Patients with PH receiving hemodialysis had a significantly higher cardiac output (6.9 L/min vs 5.5 L/min, p = 0.017). PH developed in four of six patients with normal PAP after onset of hemodialysis therapy via arteriovenous access. One-minute arteriovenous access compression in four patients decreased the mean systolic PAP from 52 +/- 7 to 41 +/- 4 mm Hg (p = 0.024). PH normalized in four of five patients receiving hemodialysis following kidney transplantation. Kaplan-Meier survival analysis according to PAP values revealed significant survival differences (p < 0.024). CONCLUSIONS: This study demonstrates a surprisingly high incidence of PH among patients with ESRD receiving long-term hemodialysis with surgical arteriovenous access. Both ESRD and long-term hemodialysis via arteriovenous access may be involved in the pathogenesis of PH by affecting pulmonary vascular resistance and cardiac output.

Adolescent↗
PubMed2003

Natural history of moderate mitral valve stenosis.

BACKGROUND: With the introduction of surgery and percutaneous balloon valvuloplasty for relieving severe mitral stenosis the natural history of the disease has markedly altered. OBJECTIVES: To determine the natural history of the disease in patients with moderate mitral valve stenosis. METHODS: Demographic, clinical and echocardiographic data were evaluated in 36 patients with moderate mitral stenosis during a follow-up of 71 +/- 15 months. RESULTS: The 36 patients comprised 32 women and 4 men with a mean age of 43.7 +/- 12.2 years; 28 were Jewish and 8 were of Arab origin. During follow-up, there was a significant decrease in mitral valve area, with an increase in mean mitral valve gradient and score. Mean loss of mitral valve area was 0.04 +/- 0.11 cm 2/year. No correlation was found between disease progression and age, past mitral valve commissurotomy, baseline mean gradient or mitral valve score. Larger baseline mitral valve area (P = 0.007) and Arab origin (P = 0.03) had an independent correlation to loss of mitral valve area. Fifteen patients (42%) did not demonstrate any loss in mitral valve area during the follow-up period. CONCLUSIONS: The rate of mitral valve narrowing in patients with moderate mitral stenosis is variable and cannot be predicted by patient's age, past commissurotomy, valve score or gradient. Secondly, larger baseline mitral valve area and Arab origin showed an independent correlation to loss of mitral valve area; and finally, in many patients valve area did not change over a long observation period.

Adult↗
PubMed2002

Failure of left ventricular hypertrophy to regress after surgery for aortic valve stenosis.

BACKGROUND: Regression of left ventricular (LV) hypertrophy usually follows surgery for aortic stenosis (AS); however, a significant number of ventricles remain hypertrophied. The extent of this phenomenon, the reasons for failure to regress, and its significance are unclear. METHODS: We investigated 43 patients before and after aortic valve surgery and divided them into two groups: 30 patients with regression of LV hypertrophy (Group A) and 13 patients without regression (Group B). Preoperative echocardiographic measurements, clinical status, and operative factors were compared between the two groups. The patients were followed up for 42 +/- 22 months for the occurrence of hospitalization for congestive heart failure (CHF) or death. RESULTS: Preoperatively, the two groups were similar except for an excess of patients in New York Heart Association (NYHA) functional Class IV and a greater incidence of old myocardial infarcts in Group B. Postoperatively, Group B patients had larger LVs with decreased systolic function. This was associated with a poor prognosis (23% mortality and 38% CHF vs 0% and 4% for Group A patients, P = 0.0002). Cox regression analysis showed previous myocardial infarction (P < 0.001) and percent mass reduction (P = 0.019) to be independent predictors of CHF or death. CONCLUSIONS: Successful regression of LV mass is difficult to predict before surgery; however, its absence is related strongly to a poor long-term prognosis.

Aged↗
PubMed2002

Cardiogenic shock complicating acute carbon monoxide poisoning despite neurologic and metabolic recovery.

We report the cases of 2 previously healthy young patients with acute carbon monoxide intoxication who deteriorated to cardiogenic shock in the face of apparent metabolic and neurologic recovery. Prolonged exposure to sublethal levels of carbon monoxide (>24 hours, carboxyhemoglobin level of 20.4% and 22.6%) and massive binding of the toxin to myocardial myoglobin and mitochondrial cytochrome chain enzymes might explain their protracted cardiac failure. The good response to inotropic agents and the findings of repeated echocardiographic studies support the probable diagnosis of myocardial stunning. Complete cardiac recovery was observed in both patients.

Adult↗
PubMed2002

Evaluation of inotropic changes in ventricular function by NOGA mapping: comparison with echocardiography.

Assessment of left ventricular (LV) function in the catheterization laboratory is important to optimize treatment decisions and guide catheter-based local therapies. NOGA electromechanical mapping was developed to assess LV contraction during catheterization; however, quantitative analysis of its "local shortening" (LS) algorithm and direct comparison with conventional methods are lacking. We evaluated the accuracy of NOGA-based regional and global function by examining its ability to detect pharmacologically induced changes in contractility compared with echocardiography. Ten anesthetized pigs were paced to ensure a constant heart rate throughout the experiment. Electromechanical maps of the LV and short-axis echocardiograms were obtained 1) at baseline, 2) during intravenous dobutamine, and 3) after intravenous propranolol. NOGA LS and ejection fraction (EF) consistently increased under dobutamine and decreased after propranolol. NOGA LS and NOGA and echocardiography circumferential shortening correlated highly with one another (r > 0.80), as did NOGA EF with echocardiography EF (r = 0.92), although absolute values differed somewhat. Thus NOGA-based global and regional function correlates closely with echocardiography and is sensitive to changes in contractility, but, at the upper end of the scale, LV function is underestimated.

Animals↗
PubMedDate not supplied

Pulmonary hypertension in hemodialysis patients: an unrecognized threat.

Pulmonary hypertension (PH) is a progressive, fatal pulmonary circulatory disease that accompanies many conditions (including left to right side shunt) with compensatory elevated cardiac output. PH also complicates chronic hemodialysis (HD) therapy immediately after the creation of an arteriovenous (AV) access, even before starting HD therapy. It tends to regress after temporary AV access closure and after successful kidney transplantation. Affected patients have significantly higher cardiac output. This syndrome is associated with a statistically significant survival disadvantage. The laboratory hallmark of this syndrome is reduced basal and stimulatory nitric oxide (NO) levels. It appears that patients with end-stage renal disease (ESRD) acquire endothelial dysfunction that reduces the ability of their pulmonary vessels to accommodate the AV access-mediated elevated cardiac output, exacerbating the PH. Doppler echocardiographic screening of ESRD patients scheduled for HD therapy for the occurrence of PH is indicated. Early diagnosis enables timely intervention, currently limited to changing dialysis modality or referring for kidney transplantation.

Arteriovenous Shunt, Surgical↗