Sudden death in mitral regurgitation due to flail leaflet.
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OBJECTIVES: We sought to assess the incidence and determinants of sudden death (SUD) in mitral regurgitation due to flail leaflet (MR-FL). BACKGROUND: Sudden death is a catastrophic complication of MR-FL. Its incidence and predictability are undefined. METHODS: The occurrence of SUD was analyzed in 348 patients (age 67 +/- 12 years) with MR-FL diagnosed echocardiographically from 1980 through 1994. RESULTS: During a mean follow-up of 48 +/- 41 months, 99 deaths occurred under medical treatment. Sudden death occurred in 25 patients, three of whom were resuscitated. The sudden death rates at five and 10 years were 8.6 +/- 2% and 18.8 +/- 4%, respectively, and the linearized rate was 1.8% per year. By multivariate analysis, the independent baseline predictors of SUD were New York Heart Association (NYHA) functional class (p = 0.006), ejection fraction (p = 0.0001) and atrial fibrillation (p = 0.059). The yearly linearized rate of sudden death was 1% in patients in functional class I, 3.1% in class II and 7.8% in classes III and IV. However, of 25 patients who had SUD, at baseline, 10 (40%) were in functional class I, 9 (36%) were in class II and only 6 (24%) in class III or IV. In five patients (20%), no evidence of risk factors developed until SUD. In patients with an ejection fraction > or =60% and sinus rhythm, the linearized rate of SUD was not different in functional classes I and II (0.8% per year). Surgical correction of MR (n = 186) was independently associated with a reduced incidence of SUD (adjusted hazard ratio [95% confidence interval] 0.29 [0.11 to 0.72], p = 0.007). CONCLUSIONS: Sudden death is relatively common in patients with MR-FL who are conservatively managed. Patients with severe symptoms, atrial fibrillation and reduced systolic function are at higher risk, but notable rates of SUD have been observed without these risk factors. Correction of MR appears to be associated with a reduced incidence of SUD, warranting early consideration of surgical repair. (+info)
Abnormal cardiac function in the streptozotocin-induced non-insulin-dependent diabetic rat: noninvasive assessment with doppler echocardiography and contribution of the nitric oxide pathway.
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OBJECTIVES: We sought to evaluate in vivo and in vitro left ventricular (LV) geometry and function in streptozotocin-induced diabetic rats and the possible role of the nitric oxide (NO) pathway. BACKGROUND: Diabetes results in cardiac dysfunction; however, the specific abnormalities are unknown. Because decreased NO contributes to abnormal vascular function in diabetics, we hypothesized that NO pathway abnormalities may contribute to diabetic cardiomyopathy. METHODS: Control rats and those with non-insulin-dependent diabetes mellitus (NIDDM) underwent echocardiography, hemodynamic assessment, isolated heart perfusion and measurement of exhaled NO and LV endothelial constitutive nitric oxide synthase (ecNOS). RESULTS: Diabetic rats had increased LV mass (3.3 +/- 0.6 vs. 2.6 +/- 0.3 g/g body weight [BW], p < 0.001) and cavity dimensions (diastolic 2.0 +/- 0.1 vs. 1.8 +/- 0.2 cm/cm tibial length [TL], p < 0.05). Diabetic rats had prolonged isovolumic relaxation time (IVRT) (40 +/- 8 vs. 26 +/- 6 ms, p < 0.0001), increased atrial contribution to diastolic filling (0.47 +/- 0.09 vs. 0.30 +/- 0.08 m/s, p < 0.0001), and elevated in vivo LV end-diastolic pressure (7 +/- 6 vs. 2 +/- 1 mm Hg, p = 0.04). Diabetic rats had increased chamber stiffness. Shortening was similar in both groups, despite reduced meridional wall stress in diabetics, suggesting impaired systolic contractility. Exhaled NO was lower in diabetic rats (1.8 +/- 0.2 vs. 3.3 +/- 0.3 parts per billion, p < 0.01) and correlated with Doppler LV filling. The ecNOS was similar between the groups. CONCLUSIONS: Diabetic cardiomyopathy is characterized by LV systolic and diastolic dysfunction, the latter correlating with decreased exhaled NO. The NO pathway is intact, suggesting impaired availability of NO as contributor to cardiomyopathy. (+info)
Gender differences in the presentation of adult obstructive hypertrophic cardiomyopathy with resting gradient: a study of 122 patients.
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The present study investigated gender differences among adult patients with obstructive hypertrophic cardiomyopathy (OHCM) and resting gradient. Using outflow gradients >10 mmHg and the presence of asymmetrical septal hypertrophy of the left ventricle as inclusion criteria, 122 patients were identified among patients referred for echocardiographic examinations between May 1990 and October 1996. Clinical, echocardiographical and follow-up data were compared between male and female patients. The female patients were significantly older than male patients (mean age +/-SD 66.7+/-10.5 vs 54.8+/-12.5 years). The female patients had a smaller interventricular septal wall thickness, less frequent systolic anterior movement of the mitral valve, more frequent association with hypertension, and less frequent association with ischemic heart disease (IHD) and giant T wave inversion. In this study population, adult female patients presented with OHCM 12 years later than males. Whether this represents female patients' reluctance to seek medical attention early, a different disease process that affects predominantly elderly females, or a gender-specific end organ response to aging, hypertension, IHD and other processes, or the protective effects of estrogen remains to be determined. (+info)
Dual-chamber pacing in hypertrophic obstructive cardiomyopathy: a comparison of acute and chronic effects.
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This study describes the acute and chronic effects of dual-chamber (DDD) pacing in 14 consecutive patients with hypertrophic obstructive cardiomyopathy (HOCM), whose symptoms were refractory to drug therapy. Although left ventricular (LV) outflow tract pressure gradients diminished from 106+/-47 to 62+/-33 mm Hg (p<0.001) by temporary pacing, the residual pressure gradients were >30 mm Hg in the majority of those with concomitant reductions in cardiac output. The DDD pacing was judged as insufficient by the acute study in the majority of patients. A dual-chamber pacemaker was, however, implanted in 11 patients, and the chronic pacing effects were evaluated. All symptoms (syncope, fainting, palpitation and dyspnea) subsided within 1 month. Left ventricular outflow tract pressure gradients diminished from 99+/-56 to 21+/-13 mm Hg (p<0.004) at 1 week after, and to 17+/-12 mm Hg (p<0.002) at 1 year after the implantation, as measured by Doppler echocardiography. Echocardiogram showed disappearance of the systolic anterior motion of the mitral valve, and significant regression of the septal hypertrophy (from 18.5+/-4.3 to 15.7+/-4.1 mm, p<0.04). There was no significant correlation between the acute and chronic pacing effects in the reduction of the pressure gradients or symptomatic improvement. These results suggest that DDD pacemaker implantation is an effective treatment without any serious risks for patients with drug-refractory HOCM. The chronic-pacing effect in the reduction of the pressure gradient, the regression of hypertrophy and symptomatic improvement cannot be predicted by the assessment of temporary DDD pacing. (+info)
Late patency of recycled internal mammary artery: verification by Doppler echocardiography and coronary angiography.
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We report the case of a 57-year-old man who had presented with exertional angina early in 1997 and had subsequently undergone myocardial revascularization with the use of both internal mammary arteries. Two months after surgery, the patient was readmitted to the hospital with unstable angina. Coronary angiography revealed a 90% occlusion of the left internal mammary artery anastomosis, which was attached to the left anterior descending coronary artery. At reoperation, the left internal mammary artery was detached from the left anterior descending coronary artery, probed and injected with papaverine, checked for patency, and regrafted to the same coronary artery. Recycling of the left internal mammary artery was facilitated by the harvesting and routing technique that had been used during the previous operation. At the patient's 1-year follow-up visit, both Doppler echocardiography and coronary angiography showed patency of the recycled graft. We conclude that recycling of the left internal mammary artery is a safe and effective option in selected patients who require reoperation after myocardial revascularization. (+info)
Patients with dilated cardiomyopathy show reduction of the somatotroph responsiveness to GHRH both alone and combined with arginine.
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OBJECTIVE: Altered function of the GH/IGF-I axis in patients with dilated cardiomyopathy (DCM) has been reported. In fact, DCM patients show reduction of IGF-I levels, which could reflect slight peripheral GH resistance or, alternatively, reduced somatotroph secretion. Spontaneous GH secretion has been reported to be altered by some but not by other authors, whereas the GH response to GHRH, but not that to GH-releasing peptides, seems reduced in DCM patients. On the other hand, it is well known that the GH response to GHRH in humans is markedly potentiated by arginine (ARG), which probably acts via inhibition of hypothalamic somatostatin release; in fact the GHRH+ARG test is known as one of the most reliable to evaluate the maximal secretory capacity of somatotroph cells. METHODS: In order to further clarify the somatotroph function in DCM, in well-nourished patients with DCM (34 male, 4 female; age (mean+/-s.e. m.) 57.8+/-1.1 years; body mass index (BMI) 24.6+/-0.6kg/m(2); left ventricular ejection fraction 23.2+/-1.6%; New York Heart Association classification I/1, II/17, III/18, IV/2) we studied the GH response to GHRH (1.0 microgram/kg i.v.) alone or combined with ARG (0.5g/kg i.v.). The results in DCM patients were compared with those in age-matched control subjects (CS) (39 male, 7 female; age 58.9+/-1.0 years; BMI 23.2+/-0.3kg/m(2)). RESULTS: Mean IGF-I levels in DCM patients were lower than in CS (144.3+/-6.9 vs 175.1+/-8. 4 microgram/l, P<0.05) whereas basal GH levels were similar in both groups (1.7+/-0.3 vs 1.7+/-0.3 microgram/l). The GH response to GHRH in DCM patients was lower (P<0.05) than that in CS (GH peak 6.5+/-1.2 vs 10.7+/-2.1 microgram/l). In both groups the GH response to GHRH+ARG was higher (P<0.001) than that to GHRH alone. However, the GH response to GHRH+ARG in DCM patients remained clearly lower (P<0.01) than that in CS (18.3+/-3.2 vs 34.1+/-4.6 microgram/l). The GH response to GHRH alone and combined with ARG was not associated with the severity of the disease. CONCLUSION: DCM patients show blunted GH responses to GHRH both alone and combined with ARG. Evidence that ARG does not restore the GH response to GHRH in DCM patients makes it unlikely that the somatotroph hyporesponsiveness to the neurohormone reflects hyperactivity of hypothalamic somatostatinergic neurons. (+info)
Right ventricular diastolic abnormalities in systemic sclerosis. Relation to left ventricular involvement and pulmonary hypertension.
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OBJECTIVES: To investigate right ventricular diastolic function in systemic sclerosis (SSc) and its relation to clinical features of the disease. METHODS: Seventy seven unselected SSc patients and 33 healthy subjects were submitted to echocardiography and echo Doppler study to assess left and right systolic as well diastolic function and to estimate maximal arterial systolic pulmonary pressure (PAP). In addition, the patients were investigated to define the SSc subset and the extent of skin and internal organ involvement. RESULTS: An abnormal right ventricular filling, as expressed by an inverted tricuspidal (Tr) E/A ratio (Tr E/A ratio <1), was detected in 31 of the 77 SSc patients (40%) and in 0 of the 36 controls ( p<0.001 ). All the 31 patients with an inverted Tr E/A ratio were found to have a PAP > 30 mm Hg. Twenty resulted to have an inverted mitral (Mit) E/A ratio (Mit E/A ratio <1), indicating an abnormal left ventricular filling. In multiple regression analysis, Tr E/A ratio resulted to be independently correlated to both PAP (r= -0.35;p<0. 003) and Mit E/A ratio (r=0.39;p<0.001). CONCLUSIONS: This study points out an impaired right ventricular filling in a significant percentage of SSc patients whatever the subset. This alteration is independently correlated to both PAP and left ventricular filling abnormalities. (+info)
Persistent ST segment depression in precordial leads V5-V6 after Q-wave anterior wall myocardial infarction is associated with restrictive physiology of the left ventricle.
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OBJECTIVES: To examine the relationship between the persistence of ST segment depression in leads V5-V6 after Q-wave anterior wall myocardial infarction (MI) and the filling pattern of the left ventricle (LV). BACKGROUND: Precordial ST segment depression predominantly in leads V5-V6 is associated with increased in-hospital morbidity and mortality after acute myocardial ischemia, perhaps due to reduced diastolic distensibility of the LV. METHODS: We prospectively studied 19 patients after Q-wave anterior wall MI (>6 months). All patients underwent 12-lead ECG recording, symptom-limited treadmill exercise testing with single photon emission computed tomography thallium-201 imaging, transthoracic Doppler echocardiography, cardiac catheterization and measurement of circulating atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels. Patients were classified based on the presence of ST segment depression in leads V5-V6: Group I = ST segment depression <0.1 mV (n = 10); Group II = ST segment depression > or =0.1 mV (n = 9). RESULTS: Patients in Group II had greater LV end diastolic pressures (32.4 +/- 6.5 mm Hg vs. 14.8 +/- 6.1 mm Hg; p = 0.0001), higher plasma ANP (44.4 +/- 47.1 pg/ml vs. 10.7 +/- 14 pg/ml; p = 0.04) and BNP levels (89.4 +/- 62.7 pg/ml vs. 23.6 +/- 33.1 pg/ml; p = 0.01), greater left atrium area (20.6 +/- 3.1 cm2 vs. 17.8 +/- 2.4 cm2; p = 0.05), lower peak atrial (A), higher early (E) mitral inflow velocities, a higher E/A ratio and a lower deceleration time (167 +/- 44 ms vs. 220 +/- 40 ms; p = 0.05). Lung thallium uptake during exercise was more common in Group II (78% vs. 10%, p = 0.04). CONCLUSIONS: Persistent ST segment depression in leads V5-V6 in survivors of Q-wave anterior wall MI is associated with increased LV filling pressure and a restrictive LV filling pattern. (+info)