Transcatheter closure of a complex postmyocardial infarction ventricular septal defect after surgical patch dehiscence.

Ventricular septal defect (VSD) complicating acute myocardial infarction is a rare but serious event carrying a high mortality. Residual shunting after emergency surgical repair is common, adversely affects prognosis and can necessitate reoperation. We describe the successful transcatheter VSD closure with the Amplatzer occluder in a 75-year old man after earlier emergency surgical repair of a VSD complicating an acute myocardial infarction. The technique and positioning of the device in a tortuous infero-apical VSD are described.

Thrombotic risk in patients with aortic bioprostheses.

Thrombosis of Mosaic aortic valve bioprostheses occurring at more than one month after surgery occurs in 0.8% (95% CI 0.33-1.67%) of patients. In the two cases reported here, each patient had risk factors for thrombus formation, namely severe left ventricular impairment in one patient, while the other patient was heterozygous for prothrombin variant G20210A. The cases were treated successfully, by thrombolytic therapy with streptokinase in the first case, and by repeat aortic valve replacement in the second case. Thrombosis of bioprosthetic valves in the aortic position is rare, and a period of anticoagulation postoperatively does not invariably protect against this serious complication. In conclusion, patients with risk factors for thrombus formation should be considered for long-term anticoagulation.

Regional wall stress predicts ventricular remodeling after anteroseptal myocardial infarction in the Healing and Early Afterload Reducing Trial (HEART): an echocardiography-based structural analysis.

BACKGROUND: Increased left ventricular (LV) wall stress after myocardial infarction (MI) has been implicated in LV remodeling. However, the relationship between LV wall stress and LV remodeling is incompletely defined. METHOD: We prospectively studied the relationship between regional wall stress and LV remodeling by application of the finite element method to end-systolic LV models from patients enrolled in the Healing and Early Afterload Reducing Therapy (HEART) Trial. Individual LV models were constructed from orthogonal apical echocardiographic views obtained at day 14 after anteroseptal MI in 64 patients. Of these, 31 patients received low-dose (0.625 mg) ramipril and 33 patients received full-dose (10 mg) ramipril. LV wall stress was calculated by the finite element method and correlated with change in LV volume from day 14 to day 90 after MI. RESULTS: Among all patients, increases in apical regional wall stress were associated with LV volume changes (P -trend =.015). The relationship between apical regional wall stress and change in LV volume was strongest in the low-dose ramipril group (r = 0.53, P =.002) and remained significant after adjustment for end-diastolic volume, infarct size, ejection fraction, and systolic blood pressure yet was attenuated in the full-dose ramipril group. CONCLUSIONS: Apical regional wall stress is an independent predictor of subsequent LV remodeling after MI. The relationship between increased apical wall stress and LV dilatation appears to be attenuated by full-dose angiotensin-converting enzyme inhibition.

Early experience with the mosaic bioprosthesis: a new generation porcine valve.

BACKGROUND: The Mosaic bioprosthesis is a new generation stented porcine valve. METHODS: Between May 1995 and April 1998, this valve was implanted in the aortic position in 98 patients (70 men; mean age, 69.2 years [34.2 to 83.6 years]). Preoperatively 35 patients were in New York Heart Association functional class 3 or 4. Fifty-nine patients underwent concomitant procedures. The mean duration at follow-up in January 1999 was 23.7 +/- 10.2 months (0.3 to 39.4 months) and totaled 193 patient-years. All but one survivor was in New York Heart Association class 1 or 2. RESULTS: Early complications included 1 death, 3 reoperations for bleeding, greater than mild regurgitation (paravalvar) in 1 patient and thromboembolism in 4 patients. Late complications included four deaths, study-valve endocarditis in 3 patients, more than mild regurgitation or hemolysis in 2, and thromboembolism in 2 patients. Late follow-up echocardiography in all survivors showed a mean transaortic gradient of 13.6 +/- 6.7 mm Hg, and an aortic valve area of 1.80 +/- 0.61 cm2. Valve replacement was followed by a significant and sustained decrease in left ventricular mass for all valve sizes. There has been no primary structural valve failure. CONCLUSIONS: The early experience with the Mosaic valve in the aortic position has been promising.

Temporal dissociation of left ventricular function and remodeling following experimental myocardial infarction in rats.

BACKGROUND: Left ventricular function early after myocardial infarction (MI) predicts subsequent clinical outcome. Nevertheless, the relationship between early changes in left ventricular function and subsequent left ventricular remodeling has not been well defined. METHODS AND RESULTS: To explore the temporal relationship between left ventricular function and remodeling after MI, rats (n = 63) underwent coronary artery ligation with and without reperfusion at 45 or 180 minutes or a sham operation. All animals were followed up by serial echocardiography preligation; 4, 24, and 48 hours; and 1, 2, 3, 4, 6, and 9 weeks after MI. Measures of global left ventricular size and function and regional wall motion were obtained at physiological heart rates. Histological infarct sizes (range, 0% to 52%) were determined in all animals. Within 4 hours of MI, fractional area change (FAC) decreased dramatically in association with an increase in left ventricular systolic cavity area, whereas diastolic area increased more gradually. Early FAC was related to infarct size (r = -0.82; P < .000), predicted the extent of left ventricular enlargement (P = .0001), and remained depressed throughout the duration of follow-up. Regional wall motion excursion and systolic wall thickness decreased in the infarcted and noninfarcted regions in animals with large infarctions. CONCLUSIONS: The rate of left ventricular dilatation after MI in rats is proportional to initial left ventricular function, although left ventricular function remains relatively constant as the ventricle progressively enlarges. Regional myocardial function after a large MI is abnormal in noninfarcted as well as infarcted regions.

Incidence and natural history of left ventricular thrombus following anterior wall acute myocardial infarction.

Previous studies have reported left ventricular (LV) thrombus in 20% to 56% of patients after anterior wall acute myocardial infarction (AMI). The Healing and Early Afterload Reducing Therapy (HEART) study was a prospective study comparing effects of early (24 hours) or delayed (14 days) initiation of ramipril, an angiotensin-converting enzyme inhibitor, on LV function after anterior wall AMI. This ancillary study assessed prevalence of LV thrombus. Two-dimensional echocardiography was performed on days 1, 14, and 90 after myocardial infarction. The cohort consisted of 309 patients. Q-wave anterior wall AMI occurred in 78%; 87% received reperfusion therapy. The prevalence of LV thrombus was 2 of 309 (0.6%) at day 1, 11 of 295 (3.7%) at day 14, and 7 of 283 (2.5%) at day 90. One patient had thrombus at 2 examinations. The day 1 echocardiogram was not correlated with thrombus development. LV size increased more in patients with thrombus than in those without thrombus. Patients with thrombus had more wall motion abnormality after day 1 than patients without thrombus (p = 0.03). Thus, the current prevalence of LV thrombus in anterior wall AMI is lower than previously reported, possibly due to changes in AMI management. Preservation of LV function is likely to be an important mechanism. Most thrombi are seen by 2 weeks after AMI. Resolution documented by echocardiography is frequent.

Early versus delayed angiotensin-converting enzyme inhibition therapy in acute myocardial infarction. The healing and early afterload reducing therapy trial.

BACKGROUND: Although ACE inhibitor therapy has been shown to reduce mortality in patients with acute myocardial infarction (MI), the optimal dose and the timing of its initiation have not been determined. METHODS AND RESULTS: In a double-blind trial of 352 patients with anterior MI, we compared the safety and effectiveness of early (day 1) versus delayed (day 14) initiation of the ACE inhibitor ramipril (10 mg) on echocardiographic measures of left ventricular (LV) area and ejection fraction (EF). An early, low-dose ramipril (0.625 mg) arm was also evaluated. Clinical events did not differ. During the first 14 days, the risk of manifesting a systolic arterial pressure of < or = 90 mm Hg was increased in both ramipril groups. LVEF increased in all groups during this period, but the early, full-dose ramipril group had the greatest improvement in EF (increase: full, 4.9 +/- 10.0; low, 3.9 +/- 8.2%; delayed, 2.4 +/- 8.8%; P for trend < .05) and was the only group that did not demonstrate a significant increase in LV diastolic area. CONCLUSIONS: The results of the present study demonstrated that in patients with anterior MI, the early use of ramipril (titrated to 10 mg) attenuated LV remodeling and was associated with a prompter recovery of LVEF. The use of low-dose regimen did not prevent hypotension and had only intermediate benefits on LV size and function. The more favorable effects on LV topography of the early use of full-dose ramipril support the results of the major clinical trials, which have demonstrated an early survival benefit of ACE inhibition.

Current incidence and determinants of perioperative myocardial infarction in coronary artery surgery.

Increasingly, patients undergoing coronary artery bypass grafting (CABG) are elders, have had previous CABG, and have poor left ventricular function. To evaluate determinants of perioperative myocardial infarction (PMI) after isolated CABG, 499 consecutive patients were reviewed. Definite PMI (total peak creatine kinase [CK] > 700 U/L, creatine kinase MB [CK-MB] > 30 ng/ml, and new pathologic electrocardiographic Q waves) occurred in 25 patients (5.0%) and probable PMI (total peak CK > 700 U/L, CK-MB > 30 ng/ml, and a new wall-motion abnormality) occurred in 10 (2.0%) patients. According to multivariate logistic regression analysis, independent risk factors for definite or probable PMI (adds ratios; 95% confidence intervals) were emergency surgery (3.1; 1.1 to 8.4; p = 0.003), aortic cross-clamp time > 100 minutes (4.2; 1.6 to 11.2; p = 0.004), myocardial infarction in the preceding week (2.6; 1.0 to 6.4; p = 0.04), and previous revascularization (2.4; 1.1 to 5.2; p = 0.02). In conclusion, both preoperative and intraoperative factors influence the risk of PMI after CABG. Despite changes in the profile of patients undergoing CABG, the incidence of PMI in this tertiary center is comparable with that found in earlier series, probably because of improvements in surgical techniques and postoperative care.

Preoperative prediction of prosthetic aortic valve annulus diameter by two-dimensional echocardiography.

Echocardiography may allow preoperative selection of appropriately sized aortic homograft valves. This study compared measurement of aortic annulus diameter from the preoperative transthoracic two-dimensional echocardiogram with prosthetic valve annulus diameter in 178 consecutive patients under-going primary aortic valve replacement. Aortic annulus diameter was measured independently from the two-dimensional parasternal long axis view by two experienced observers blinded to the size of valve implanted. Mean annulus diameter from three end-diastolic frames was recorded. Of the 178 patients, 124 (70%) of Observer 1 measurements and 102 (57%) of Observer 2 measurements were within 2mm of valve annulus diameter (p < 0.0001 for both observers). Six percent of Observer 1 measurements and 12% of Observer 2 measurements were more than 4mm away from valve annulus diameter. The echocardiographic prediction of valve size corresponded to actual prosthetic valve annulus diameter in 69 patients (39%) for Observer 1 and 60 patients (34%) for Observer 2. The percentages of echocardiographic measurements within two millimeter of valve annulus diameter were significantly different for the two observers (p < 0.05). The percentages of echocardiographic measurements within two millimeter of valve annulus diameter in 39 patients without significant aortic valve calcification were not significantly different from the remaining 139 patients with calcified valves. The interobserver coefficient of variation was 6.2% and the intraobserver coefficient of variation was 4.3%. Although preoperative measurement of aortic annulus diameter from transthoracic echocardiography approximates prosthetic valve annulus diameter in the majority of patients undergoing primary aortic valve replacement, a significant minority of estimates may be inaccurate, even in the absence of heavy calcification.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of fosinopril on cardiac and metabolic parameters in patients with NIDDM.

OBJECTIVE: To determine whether the angiotensin-converting enzyme (ACE) inhibitor fosinopril can favorably alter cardiac function in non-insulin-dependent diabetes mellitus NIDDM) patients who have either normal blood pressure (BP) or mild, untreated hypertension. RESEARCH DESIGN AND METHODS: Fifty-five NIDDM subjects with normal BP or mild, untreated hypertension were randomized to treatment with the ACE-inhibitor fosinopril or placebo for 6 months in a randomized, double-blind trial to determine the effect of fosinopril on echocardiographic measurements. RESULTS: Left ventricular mass index (LVMI) fell by 6.5 +/- 4.7% (mean +/- SD) with fosinopril and increased by 8.6 +/- 3.5% during placebo treatment (P < 0.02), and isovolumic relaxation time improved significantly in those with elevated baseline levels (P = 0.02). Systolic BP fell significantly, but this did not correlate with the change in LVMI, suggesting a possible direct action of fosinopril on the heart. CONCLUSIONS: Fosinopril appears to have significant cardiac benefits in patients with NIDDM who have normal or mildly elevated BP. These benefits are achieved without adversely affecting renal status and without impairing metabolic control of diabetes.

Determinants of left ventricular hypertrophy and systolic dysfunction in chronic renal failure.

To evaluate determinants of left ventricular hypertrophy (LVH) and left ventricular (LV) systolic dysfunction in chronic renal failure (CRF), M-mode and two-dimensional echocardiography were performed in 38 undialyzed patients with CRF (serum creatinine > or = 3.4 mg/dL), 54 patients receiving continuous ambulatory peritoneal dialysis, 30 patients receiving hemodialysis, and 59 healthy age- and sex-matched volunteers. Left ventricular (LV) wall thickness and LV dimensions were greatest in dialysis patients, intermediate in CRF patients, and least in control subjects. LV mass index calculated from M-mode measurements was 78.7 g/m2 +/- 14.8 g/m2 in controls, 120.5 g/m2 +/- 28.7 g/m2 in CRF patients, and 136 +/- 45.0 g/m2 in dialysis patients (P < 0.0001). LV fractional shortening and LV velocity of circumferential shortening were lower in dialysis patients than in CRF patients and controls (fractional shortening 36.5% +/- 5.6% in controls, 36.2% +/- 7.2% in CRF patients, and 29.8% +/- 8.9% in dialysis patients; P < 0.0001). Echocardiography was normal in only 24 dialysis patients (29%) and 14 CRF patients (37%) (P = NS). Thirty-nine dialysis patients (46%) and 10 CRF patients (26%) had LVH (P = NS). Thirty dialysis patients (36%) and five CRF patients (13%) had LV systolic dysfunction (P < 0.05). LV hypertrophy with LV systolic dysfunction was present in 15 dialysis patients but no CRF patients (P < 0.05). There were no significant differences between hemodialysis patients and continuous ambulatory peritoneal dialysis patients in M-mode echocardiographic measurements or the frequency of LVH and LV systolic dysfunction.(ABSTRACT TRUNCATED AT 250 WORDS)

Simvastatin therapy for hypercholesterolaemia in patients with coronary heart disease.

The efficacy of simvastatin therapy for hypercholesterolaemia was evaluated in 26 patients with coronary heart disease, 20 of whom had undergone coronary artery bypass grafting. Simvastatin reduced total- and low-density lipoprotein (LDL) cholesterol from 8.3 to 5.1 (38%) and 6.3 to 3.3 mmol/L (48%) respectively, p less than 0.001; high-density lipoprotein (HDL) cholesterol increased from 1.19 to 1.24 mmol/L, p = NS. The changes in apoproteins A1 and B paralleled those of HDL- and LDL-cholesterol. There were no clinically important adverse effects. We conclude that simvastatin is effective lipid lowering therapy and can be used safely, in the short term, in patients with coronary heart disease.

Inheritance of hypertrophic cardiomyopathy: a cross sectional and M mode echocardiographic study of 50 families.

To determine the mode of inheritance of hypertrophic cardiomyopathy 193 first degree relatives (parents, siblings, and offspring) of 50 patients with hypertrophic cardiomyopathy were assessed by clinical examination, electrocardiography, M mode and cross sectional echocardiography, and necropsy when available. Thirty nine (20%) first degree relatives had hypertrophic cardiomyopathy--37% of parents, 25% of siblings, and 8% of offspring. Eight (23%) of 35 affected relatives diagnosed by echocardiography had normal clinical and electrocardiographic findings. In the total study group 43% of the male population and 30% of the female population were affected. This difference is statistically significant. In 28/50 families there was familial occurrence of hypertrophic cardiomyopathy. Familial occurrence was demonstrated in 17 of 18 families in which five or more family members were assessed. In 15 families the pattern of inheritance was consistent with an autosomal dominant trait; in the other 13 the affected members were identified in a single generation and the pattern of inheritance could not be determined.