Septal Ablation Versus Surgical Myomectomy for Hypertrophic Obstructive Cardiomyopathy.

PURPOSE OF REVIEW: Patients with hypertrophic cardiomyopathy (HCM) who have left ventricular outflow tract obstruction (LVOTO) often experience severe symptoms and functional limitation. Relief of LVOTO can be achieved by two invasive interventions, i.e., surgery myectomy and alcohol septal ablation (ASA), leading in experienced hands to a dramatic improvement in clinical status. Despite extensive research, however, the choice of the best option in individual patients remains challenging and poses numerous clinical dilemmas. RECENT FINDINGS: Invasive strategies have been recently incorporated in recommendations for the diagnosis and treatment of HCM on both sides of the Atlantic. These guidelines are based on a bulk of well-designed but retrospective studies as well as on expert opinions. Evidence now exists that adequate evaluation and management of HCM requires a multidisciplinary team capable of choosing the best available options. Management of LVOTO still varies largely based on local expertise and patient preference. Following the trend that has emerged for other cardiac diseases amenable to invasive interventions, the concept of a "HCM heart team" is coming of age.

Once versus twice daily enoxaparin for the initial treatment of acute venous thromboembolism.

Essentials In venous thromboembolism (VTE), it is uncertain if enoxaparin should be given twice or once daily. We compared the 15- and 30-day outcomes in VTE patients on enoxaparin twice vs. once daily. Patients on enoxaparin once daily had fewer major bleeds and deaths than those on twice daily. The rate of VTE recurrences was similar in both subgroups. SUMMARY: Background In patients with acute venous thromboembolism (VTE), it is uncertain whether enoxaparin should be administered twice or once daily. Methods We used the RIETE Registry data to compare the 15- and 30-day rates of VTE recurrence, major bleeding and death between patients receiving enoxaparin twice daily and those receiving it once daily. We used propensity score matching to adjust for confounding variables. Results The study included 4730 patients: 3786 (80%) received enoxaparin twice daily and 944 once daily. During the first 15 days, patients on enoxaparin once daily had a trend towards more VTE recurrences (odds ratio [OR], 1.79; 95% confidence interval [CI], 0.55-5.88), fewer major bleeds (OR, 0.42; 95% CI, 0.17-1.08) and fewer deaths (OR, 0.32; 95% CI, 0.13-0.78) than those on enoxaparin twice daily. At day 30, patients on enoxaparin once daily had more VTE recurrences (OR, 2.5; 95% CI, 1.03-5.88), fewer major bleeds (OR, 0.40; 95% CI, 0.17-0.94) and fewer deaths (OR, 0.58; 95% CI, 0.33-1.00). On propensity analysis, patients on enoxaparin once daily had fewer major bleeds at 15 (hazard ratio [HR], 0.30; 95% CI, 0.10-0.88) and at 30 days (HR, 0.16; 95% CI, 0.04-0.68) and also fewer deaths at 15 (HR, 0.37; 95% CI, 0.14-0.99) and at 30 days (HR, 0.19; 95% CI, 0.07-0.54) than those on enoxaparin twice daily. Conclusions Our findings confirm that enoxaparin prescribed once daily results in fewer major bleeds than enoxaparin twice daily, as suggested in a meta-analysis of controlled clinical trials.

Identification of de novo mutations and rare variants in hypoplastic left heart syndrome.

Hypoplastic left heart syndrome (HLHS) is one of the most severe congenital heart malformations, characterized by underdevelopment of the structures in the left heart-aorta complex. The majority of cases are sporadic. Although multiple genetic loci have been tentatively implicated in HLHS, no gene or pathway seems to be specifically associated with the disease. To elucidate the genetic basis of HLHS, we analyzed 53 well-characterized patients with isolated HLHS using an integrated genomic approach that combined DNA sequencing of five candidate genes (NKX2-5, NOTCH1, HAND1, FOXC2 and FOXL1) and genome-wide screening by high-resolution array comparative genomic hybridization. In 30 patients, we identified two novel de novo mutations in NOTCH1, 23 rare patients inherited gene variants in NOTCH1, FOXC2 and FOXL1, and 33 rare patients mostly inherited copy-number variants. Some of the identified variations coexisted in the same patient. The biological significance of such rare variations is unknown, but our findings strengthen the role of NOTCH pathway in cardiac valve development, indicating that HLHS is, at least in part, a 'valve' disease. This is the first report of de novo mutations associated with isolated HLHS. Moreover, the coexistence of multiple rare variants suggests in some cases a cumulative effect, as shown for other complex disease.

Common genetic markers and prediction of recurrent events after ischemic stroke in young adults.

BACKGROUND: Scarce information is available on the usefulness of new prediction markers for identifying young ischemic stroke patients at highest risk of recurrence. METHODS: The predictive effect of traditional risk factors as well as of the 20210A variant of prothrombin gene, the 1691A variant of factor V gene, and the TT677 genotype of the methylenetetrahydrofolate reductase (MTHFR) gene on the risk of recurrence was investigated in a hospital-based cohort study of 511 ischemic stroke patients younger than 45 years followed up for a mean of 43.4 months. Outcome measures were fatal/nonfatal myocardial infarction, ischemic stroke, or TIA. Risk prediction was assessed with the use of the concordance c (c index), and the Net Reclassification Improvement (NRI). RESULTS: The risk of recurrence increased with increasing number of traditional factors (hazard ratio [HR] 2.29, 95% confidence interval [CI] 1.57-3.35 for subjects with 1 factor: HR 5.25, 95% CI 2.45-11.2 for subjects with 2), as well as with that of predisposing genotypes (HR 1.96, 95% CI 1.33-2.89 for subjects carrying 1 at-risk genotype; HR 3.83, 95% CI 1.76-8.34 for those carrying 2). The c statistics increased significantly when the genotypes were included into a model with traditional risk factors (0.696 vs 0.635, test z = 2.41). The NRI was also significant (NRI = 0.172, test z = 2.17). CONCLUSIONS: Addition of common genetic variants to traditional risk factors may be an effective method for discriminating young stroke patients at different risk of future ischemic events.

Outcome of patients listed for heart transplantation after a failed surgical ventricular restoration procedure.

Patients with end-stage ischemic cardiomyopathy (IHD) and left ventricular (LV) dilatation are increasingly treated by means of surgical ventricular restoration (SVR). In some patients, SVR can delay heart transplantation (HTX). We retrospectively analyzed our experience, trying to ascertain whether HTX after a failed SVR (fSVR) carried a greater mortality risk. Since 1985, we performed 742 HTX. Since June 1999, 133 IHD patients were listed for HTX. We assigned them to 3 groups: (A) not a redo (n=54); (B) redo after coronary artery bypass grafting (n=54); and (C) redo after fSVR (n=25). Respectively, 37, 33, and 12 patients underwent HTX with in-hospital mortality after HTX of 4/37 (10.8%), 12/33 (36.4%), and 2/12 (16.7%). Mortality on the list was 9/54 (16.7%), 11/54 (20.4%), and 7/25 (28.0%) respectively. Removal from the list occurred in 4, 5, and 2 patients, and 4, 5, and 4 patients are still awaiting HTX, respectively. In group C, the mean time from SVR to HTX list was 45.6+/-43.3 months, and list mortality occurred after 5.83+/-5.81 months. In-hospital mortality in both patients of group C was due to the occurrence of multisystem organ failure; 10/12 were extubated after 19.3+/-9.6 hours and discharged from the intensive care unit after 3.9+/-1.6 days. The recorded complications were: 3 acute renal failure, 1 pericardial effusion, and 2 episodes of acute rejection. Since only 5/25 patients with fSVR had undergone SVR at our institution, we cannot establish which patients were really eligible for HTX at the time of SVR. Our experience showed that patients listed for HTX displayed a high list mortality, but that HTX after a failed SVR did not seem to have a poorer outcome than HTX after previous conventional CABG.

Percutaneous bridge to heart transplantation by venoarterial ECMO and transaortic left ventricular venting.

We report a case in which life support for cardiogenic shock was achieved by a nonpulsatile venoarterial bypass, and left ventricular decompression was obtained by a catheter placed percutaneously through the aortic valve into the left ventricle. The blood drained from the left ventricle was pumped into the femoral artery. The normalization of left heart filling pressures allowed the resolution of pulmonary edema, and the patient underwent a successful heart transplantation following 7 days of mechanical cardiocirculatory support.

Mitral valve repair and transesophageal echocardiographic findings in a high-risk subgroup of patients with active, acute infective endocarditis.

BACKGROUND AND AIM OF THE STUDY: Limited data are available regarding the efficacy of mitral valve repair in patients affected by active, acute infective endocarditis. In addition, the predictivity of transesophageal echocardiography (TEE) for guiding the surgical decision-making process in these patients has not yet been reported. The study aim was to evaluate the long-term results of mitral valve repair and role of TEE in active, acute infective endocarditis. METHODS: The study population consisted of patients affected by infective endocarditis of the mitral valve who underwent surgery. TEE was performed intraoperatively to guide the best surgical approach. All patients were followed up (mean 73+/-8 months) after surgery. RESULTS: Twenty-eight patients underwent surgery for infective endocarditis; of these, 13 had mitral valve repair for active, acute infective endocarditis and formed the basis of the study. Sensitivity, specificity, positive predictive value, negative predictive value of TEE in detecting the mechanism of mitral regurgitation were 87%, 100%, 100% and 92%, respectively. The predictivity test of TEE in guiding surgical strategy was 94%. All patients were alive at the time of follow up; 10 (77%) were in NYHA class I and three in class II (23%). Mitral regurgitation was severe in one patient (8%), moderate in three (23%), mild in four (31%), and absent in five (38%). No relapses of active infective endocarditis were observed during the follow up period. CONCLUSION: Mitral valve repair appears to be an effective treatment for active, acute infective endocarditis with mitral regurgitation and should be considered as a therapeutic strategy when surgery is contemplated. TEE has a fundamental role in the surgical decision-making process in these patients.

Measurement of brain natriuretic peptide in plasma samples and cardiac tissue extracts by means of an immunoradiometric assay method.

We evaluated the analytical characteristics and clinical usefulness of a commercial immunoradiometric assay (IRMA) kit for brain natriuretic peptide (BNP). Mean (+/-SD) plasma BNP concentrations measured in 129 normal subjects were 2.9+/-2.7 pmol/l (median 2.2 pmol/l; range 0.1-12.4 pmol/l). The mean (+/- SD) value observed in healthy men (2.1 +/- 2.0 pmol/l, n = 49) was significantly (p=0.0009) different to that found in women (3.4 +/- 2.9 pmol/l, n=80). A positive relationship (R=0.214, p=0.0174) was found between BNP values and age. In 65 patients with cardiac diseases, BNP levels increased with the progression of clinical severity of disease; patients with more severe disease [NYHA functional class III-IV, mean (+/- SD) BNP +/- 254 +/- 408 pmol/l, n=22] showed significantly (p<0.0001) increased values compared to patients with mild symptoms of disease (NYHA functional class I-II, mean (+/- SD) BNP=19.6 +/- 17.2 pmol/l, n=43). Furthermore, in 32 patients with chronic renal failure, greatly increased (p<0.0001) BNP values were found both before (mean +/- SD=88. 1+/- 111.1 pmol/l) and after haemodialysis (mean +/- SD=65.6 +/- 76.7 pmol/l), with a significant reduction after haemodialysis (p=0.0004) compared to pre-haemodialysis. The mean (+/- SD) BNP value found in atrial extracts collected during aorto-coronary bypass operations in 15 patients was 14.5 +/- 51.9 pmol/g of cardiac tissue. Moreover, the mean (+/- SD) tissue levels of BNP in 7 heart transplant recipients were 128.4 +/- 117.2 pmol/g of cardiac tissue in atrium, 68.4 +/- 76.7 pmol/g in ventricle, and 10.9 +/- 8.5 pmol/g in interventricular septum. Finally, BNP values found in cardiac tissues of two subjects collected at autopsy were considerably lower (on average 1/1000) than those observed in cardiac tissues of patients with cardiac diseases. The IRMA method for BNP determination evaluated in this study showed a good degree of sensitivity, precision and practicability. Therefore, this method should be a reliable tool for the measurement of plasma BNP levels for both experimental studies and routine assay.

A study of iodothyronine 5'-monodeiodinase activities in normal and pathological tissues in man and their comparison with activities in rat tissues.

The present study was undertaken to investigate the peripheral iodothyronine 5'-monodeiodination in different human and rat tissues. We studied iodothyronine 5'-monodeiodinase type I (5'-DI) activity in liver, kidney, intestine, right cardiac atrium and skeletal muscle and we compared the results with those in rat tissues. Lodothyronine 5'- monodeiodinase type II (5'-DII) activity was studied in normal and ischemic human heart and in rat normal myocardium and brain. The 5'-DI activity (fmol/min x mg protein) in liver and kidney was significantly higher (p < 0.001, ANOVA) in normal rat tissue than in human. However, no significant differences were observed in 5'-DI activity between normal and tumoral human intestine or between intestinal tissue of man and rat. 5'-DI activity in normal human skeletal muscle was significantly higher than that in rat skeletal muscle (p < 0.05). The 5'-DI activity was lower in human ischemic myocardium when compared to normal myocardium either in humans (p < 0.05) or rat (p < 0.001). The Km of 5'-DI was significantly lower in rat than in human kidney and liver (p < 0.05). We conclude that 1) 5'-DI is distributed widely among extrathyroidal human and rat tissues and 5'-DII activity is detectable both in human and rat heart; 2) 5'-DI activity in liver and kidney is lower in man than in rat; 3) 5'-DI activity in the skeletal muscle is higher in man than in the rat; 4) 5'-DI activity is decreased in tumoral tissues of human liver and kidney and in ischemic myocardium, while no significant difference was found between human and rat cardiac 5'-DII activity.

Preoperative assessment of coronary artery disease in aortic stenosis: a dipyridamole echocardiographic study.

BACKGROUND: The aim of this study was to establish the feasibility, safety, and diagnostic accuracy of the dipyridamole echocardiography test in patients with severe aortic valve stenosis for noninvasive detection of coexisting coronary artery disease. METHODS: The high-dose dipyridamole echocardiography test was performed in 52 patients with severe aortic stenosis; all patients also underwent coronary angiography, independent of test results, before cardiac operation. RESULTS: The dipyridamole echocardiography test was completed without major complications. One patient had transient atrial fibrillation that was reversed by aminophylline. Thirty-one patients (60%) had a negative test result; all had normal coronary arteries. Ten of the 21 patients (48%) with a positive test result had coexisting coronary artery disease. The positive predictive value of the dipyridamole echocardiography test for detection of coronary disease in patients with severe aortic stenosis was 48%. The negative predictive value was 100%. The sensitivity was 100% and the specificity was 74%. CONCLUSIONS: Dipyridamole echocardiography is a safe and feasible tool in patients with severe aortic stenosis eligible for a cardiac operation. A negative test result reliably rules out a significant stenosis, whereas a positive one is much less accurate in predicting coronary artery disease.

The risk of coronary artery disease after heart transplantation is increased in patients receiving low-dose cyclosporine, regardless of blood cyclosporine levels.

BACKGROUND: Coronary artery disease (CAD) of allografted hearts is the main cause of late mortality after cardiac transplant, but its etiology is still undetermined. HYPOTHESIS: This study was undertaken to evaluate the relevance of several risk factors, including cyclosporine (CsA) dose and blood CsA levels, to the incidence of CAD. METHODS: In 163 heart transplants performed between November 1985 and August 1994 at our Institution, CAD was diagnosed by coronary angiography or at postmortem examination. Patients in whom postmortem examination or coronary angiography was not performed, as well as those < 15 years of age and those who died within 1 month of surgery, were excluded from the study. The following risk factors were analyzed: recipient age, gender, pretransplant diagnosis, donor age, number of human leukocyte antigen (HLA)-AB mismatches, cytomegalovirus serology, mear serum cholesterol and triglyceride levels, the number of treated acute rejections, mean weighted CsA dose (CsA dosew and weighted blood CsA levels (blood CsA levelw). RESULTS: Coronary artery disease was diagnosed in 32 patients (19.6%). A low mean CsA dosew was the only significant predictor for CAD at multivariate analysis (p < 0.01): there was no correlation with blood CsA levelw. In the patients receiving a CsA dosew > 4 mg/kg/day, the 8.9 year probability of their remaining CAD free was 69% [confidence interval (CI) 50-87%] in comparison with 31% (CI 0-65%) in patients receiving a CsA dosew < 4 mg/kg/day. CONCLUSION: In our experience, a low CsA maintenance dose is the main risk factor for CAD, irrespective of blood CsA levels.

Medical treatment of end-stage heart failure.

Congestive heart failure is a lethal condition that affects an increasing number of patients. In recent years a great amount of data have accumulated on the pathophysiology and medical and surgical therapy of this condition. In spite of the advances in its management and the great number of patients affected, common errors are still made by internists and cardiologists in the use of drugs and therapeutic strategies. Digitalis has only recently been shown to affect hemodynamics, exercise capacity, and clinical symptoms, but the effects on survival still have to be demonstrated. Loop diuretics, eventually combined with thiazides and antialdosterone drugs in patients with clinical signs and symptoms of fluid retention, are the mainstays of therapy of congestive heart failure. In order to make diuretic therapy efficacious, moderate salt and water intake restriction is mandatory. Angiotensin-converting enzyme (ACE) inhibitors are now considered unavoidable drugs in the management of heart failure, and an attempt to reach the doses that have been shown to be efficacious for survival in the large trials has to be made in every patient with this condition. Other vasodilators, such as hydralazine and nitrates, which show a less pronounced effect on survival but more effective hemodynamic actions than ACE inhibitors, may be used to control mitral insufficiency or to improve hemodynamics in very sick patients. Hemodynamic instability refractory to increasing doses of vasodilators and diuretics is a severe condition that requires hospital admission to administer drugs parenterally. These patients are usually treated with the combination of catecholamines and phosphodiesterase inhibitors associated with intravenous diuretics until clinical stability is again achieved and oral therapy is resumed and restructured. The use of aggressive pharmacological therapy and phosphodiesterase inhibitors has reduced the need for assisted circulatory support in these patients. Beta-blockers have shown promising results when administered to patients with heart failure, although a definitive demonstration of their effects on survival is still lacking. Other additional measures that need to be considered in patients with end-stage congestive heart failure are the use of antiarrhythmic drugs and anticoagulation.

Acute enoximone effect on systemic and renal hemodynamics in patients with heart failure.

Patients with heart failure generally show improvement in their clinical condition after enoximone infusion over the period of treatment; this effect cannot be ascribed only to the known hemodynamic action of this drug. Thirty-six patients (age range 44-82 years) with heart failure (NYHA class II-IV) underwent 48-hour enoximone infusion to study whether this prolonged improvement might depend on changes in systemic or renal hemodynamics or in neurohormonal balance. All patients underwent Swan-Ganz hemodynamic monitoring; renal plasma flow, glomerular filtration rate, plasma atrial natriuretic factor (ANF), and plasma renin activity (PRA) were all measured at baseline, at the peak of the enoximone action, and 48 hours after drug discontinuation. The main hemodynamic parameters were significantly improved during enoximone infusion and after drug discontinuation. The cardiac index basal value of 2.2 +/- 0.1 l/min/m2 increased to 3.1 +/- 0.1 l/min/m2 after 24-hour therapy (p < 0.01); similarly, pulmonary wedge pressure, mean pulmonary arterial pressure, and right atrial pressure decreased markedly (p < 0.01). Beneficial effects were also observed in renal hemodynamics; indeed, renal plasma flow (basal value 485 +/- 39 ml/min) increased significantly after 24-hour enoximone infusion (575 +/- 35 ml/min; p < 0.01), and this tendency was also observed 48 hours after drug discontinuation. No significant modifications were observed in plasma hormone data; however, the PRA plasma level had a tendency to decrease. We conclude that in patients with heart failure, enoximone infusion has a less marked effect on renal hemodynamics, but this is more lasting than systemic hemodynamic effects. The tendency of PRA to decrease (although not statistically significant), still detectable 2 days after treatment in the presence of steady high plasma ANF concentrations, may also contribute to the paradoxical longlasting benefit despite the short-lived improvement in systemic hemodynamics after brief cycles of enoximone infusion.

Preliminary results of intrathymic injection of donor cells to prevent acute rejection in human heart transplantation.

In rodents, the intrathymic injection of donor cells or major histocompatibility complex peptides induces indefinite survival of a subsequent allograft with little or no immunosuppression. Here, experiments have been performed in two patients with cardiac transplantation to establish (1) the safety and tolerability of the intrathymic injection of donor leukocytes at the time of transplant surgery and (2) whether conventional immunosuppression interfered with the process of the thymic recognition of alloantigens. It was shown that the intrathymic inoculation of donor cells is safe and can be done without undesired effects. However, the procedure, as performed, did not protect from acute graft rejection. There are data enough to attribute the failure of the thymus technique in these two patients to the concomitant use of immunosuppressants. The results of this study are relevant for future trials aimed at finding the appropriate experimental conditions for the use of the thymic approach in human organ transplantation.

Reduction of haemorrhagic complications during mechanically assisted circulation with the use of a multi-system anticoagulation protocol.

Two different anticoagulation protocols were used in 49 consecutive patients mechanically supported either for bridge to transplantation (11) or for recovery of myocardial function after cardiac surgery (35). In 46 patients a Biomedicus centrifugal pump was used and in 3 patients a Pierce-Donachy ventricles. Mechanical support was provided to the left ventricle in 14 patients, to the right ventricle in 6 and to both ventricles in 12 patients; an extra-corporeal membrane oxygenator (ECMO) support was used in 17 patients. Thirty-seven males and 12 females, aged 0.2 to 58 years, were supported for an average time of 6.3 days (range 1-43). Anticoagulation was either based on a continuous infusion of heparin in the first 27 patients (group A) or on a multi-system therapy ("La Pitié" protocol) in the other 22 patients (group B). Overall survival rate was 47%. Patients in group A had a 30% (8/27) survival rate, whereas in group B a 68% (15/22) survival rate was observed (p = 0.006). Transplantation and ventricular assist device (VAD) removal was successfully obtained in 59% (16/27) and 91% (20/22) of patients in group A and group B respectively (p = 0.05). Significant bleeding occurred in 21 patients (81%) in group A and in 2 (9%) of group B (p = 0.001). In these patients bleeding averaged 230 +/- 231 ml/kg in group A versus 55 +/- 18 ml/kg in group B (p = 0.001). Surgical revision was necessary for cardiac tamponade or persistent bleeding in 12 patients of group A (25 procedures: mean 0.9/patient) and in 3 patients of group B (one each patient: mean 0.1/patient) (p = 0.01). Infection, thrombo-embolism and brain hemorrhage were also less frequent in group A than in group B. Our data suggest that the "La Pitié" protocol provides a better control of bleeding than the conventional heparin infusion in patients receiving assist device. this reduction in thrombo-hemorrhagic complications might improve the results of mechanical circulatory support.