Surgical treatments for heart failure

The surgical options for CHF are a part of a larger paradigm shift in management. Viable and effective surgical options other than cardiac transplant and ventricular assist devices clearly exist and are applicable to a large portion of patients with CHF. These surgical therapies are of acceptable risk before decompensated CHF develops. The rapidly evolving therapies for altering LV remodeling, which underlies CHF progression, are an exciting area that may be joined in the future by molecular advances in myoblast transfer and gene therapy. These therapies are the basis of the discipline of CHF surgery within cardiovascular surgery.

Relationship between plasma level of cardiotrophin-1 and left ventricular mass index in patients with dilated cardiomyopathy

OBJECTIVES

The study evaluated the relationship between plasma cardiotrophin-1 (CT-1) concentration and left ventricular (LV) mass in dilated cardiomyopathy (DCM) patients with congestive heart failure (CHF).

BACKGROUND

Cardiotrophin-1 is a newly identified member of the interleukin-6 (IL-6) family of cytokines and one of the endogenous ligands for gp130 signaling pathways in the heart, and it has potent hypertrophic and survival effects on cardiac myocytes. However, the clinical significance of CT-1 is poorly understood.

METHODS

We measured the plasma CT-1 level in 51 consecutive patients with DCM. Patients were classified into two groups: small LV mass index group and large LV mass index group, based on the median level of LV mass index.

RESULTS

The plasma CT-1 level was increased in DCM patients with the severity of CHF and was significantly higher in the large LV mass group than in the small LV mass group, despite the absence of a difference in LV ejection fraction between the two groups. In addition, there was a significant positive correlation between the plasma CT-1 level and the LV mass index (r = 0.627, p < 0.0001). According to stepwise multivariate analyses among hemodynamic and neurohumoral factors, a high plasma CT-1 level showed an independent and significant positive relationship with a large LV mass index in patients with DCM.

CONCLUSIONS

These results indicate that the plasma CT-1 level is increased in patients with DCM and is significantly correlated with the LV mass index, suggesting that CT-1 plays an important role in structural LV remodeling in patients with DCM.

The mid-term results of ventricular containment (ACORN WRAP) for end-stage ischemic cardiomyopathy

The acorn cardiac support device (ACSD) is a device designed to treat heart failure by containing the heart to prevent further dilation. Six patients with symptomatic heart failure due to ischemic cardiomyopathy were treated surgically with ACSD. All patients simultaneously underwent coronary artery bypass grafting. Ventricular reconstruction was also performed in 5 of the 6 patients. We followed up the patients for 12 months postoperatively, monitoring the left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), mitral regurgitation, and NYHA classification. Both the LVEDD and LVESD were significantly improved one month postoperatively (from 63.2 to 50.6 mm, p=0.004, and from 51.6 to 39.5 mm, p=0.025, respectively). These dimensions did not change significantly over the next 11 months. NYHA functional class improved significantly from a mean of 3 to 1.4 at 12 months (p=0.012). Mitral regurgitation improved from a mean of 2.7 preoperatively to 1.4 at 12 months and the average LVEF also improved from 27% preoperatively to 35.9% at 12 months after surgery. However these latter two results were not statistically significant. There were no late deaths and no readmissions for heart failure. Repeat coronary angiography at 6 months revealed patent grafts in all patients. The mid-term results of ACSD for patients with symptomatic heart failure suggest that ventricular containment may be useful for preventing further cardiac dilation in patients with ischemic cardiomyopathy. Randomized, long-term studies are needed to assess the efficacy and possible role of ASCD in the future management of heart failure.

Clinical value of lung uptake of iodine-123 metaiodobenzylguanidine (MIBG), a myocardial sympathetic nerve imaging agent, in patients with chronic heart failure

This study investigated the clinical value of I-123 MIBG pulmonary accumulation and washout in patients with chronic heart failure (CHF). Nineteen patients with CHF and 15 normal volunteers (NL) were included. The uptake ratio of heart to mediastinum (H/M), that of lung fields to mediastinum (L/M), and washout rate (WR) of the heart and lung fields were calculated in anterior planar images and compared with results of echocardiography and cardiac catheterization. In the CHF group, the lung uptake in delayed images increased and lung WR was decreased, suggesting pulmonary endothelial lesions. Furthermore, there was a negative correlation between right and left lung WR and pulmonary arterial diastolic pressure (PA(D)) and pulmonary arterial systolic pressure (PA(s)) in the CHF group. Since the WR of MIBG reflected PA, it may be used as an index of severity of cardiac dysfunction.

Left ventriculoplasty for nonischemic dilated cardiomyopathy

Surgical treatment of nonischemic dilated cardiomyopathy is a new field in cardiac surgery. Although current pharmacologic therapy has shown improved survival rates, many patients still need heart transplantation. To reduce the shortage of donors, there is a demanding need for effective nontransplant cardiac surgery. In the past 5 years, partial left ventriculectomy (PLV) has emerged with initial enthusiasm, but is not used because of high surgical mortality and late return of heart failure. There are several examples of improved clinical status and ventricular function with the procedure. By refining patient selection and surgical modification, ventriculoplasty will become a realistic option in the treatment of heart failure caused by nonischemic cardiomyopathy.

Surgical anterior ventricular endocardial restoration (SAVER) for dilated ischemic cardiomyopathy

Anterior infarction changes ventricular shape and volume. Akinesia is most commonly observed after early reperfusion. Dyskinesia develops in the absence of reperfusion. Both produce heart failure by dysfunction of the remote muscle. Traditional surgery deals with dyskinesia. This study evaluates surgical anterior ventricular endocardial restoration (SAVER), an operation that excludes the apical and septal scar in both akinesia and dyskinesia. A new international group of cardiologists and surgeons from 13 centers, the RESTORE Group) investigated SAVER in ischemic cardiomyopathy following anterior infarction. From January 1998 to July 2000, 662 patients underwent surgery. Early and 3-year outcomes were investigated. Concomitant procedures included coronary artery bypass grafting (CABG) in 92%, mitral repair in 22%, and mitral replacement in 3%. Hospital mortality was 7.7%. Mortality among 606 patients with SAVER and CABG alone was 4.9%. It was 8.1% among 147 patients who underwent concomitant mitral valve repair. Few patients required IABPs (8.4%), LVADs (0.4%), or ECMO (0.6%). Postoperatively, ejection fraction increased from 29.7% +/- 11.3% to 40.0% +/- 12.3% and left ventricular end systolic volume decreased from 96 +/- 63 to 62 +/- 39 mL/m(2) (P <. 05). At 3 years, the survival rate was 89.4% +/- 1.3%. Survival was lower among those with preoperative volume >80 mL/m(2) compared with volume < or = 80 mL/m(2) (83.5% +/- 3.3% v 94.5% +/- 2.0%). Freedom from readmission to hospital for heart failure was at 88.7% at 3 years and was not related to preoperative volume. SAVER is a safe and effective procedure for treating the remodeled dilated anterior ventricle following anterior myocardial infarction.

[Cardiomyopathy during clozapine therapy]

A 45-year-old woman of Moroccan origin developed a dilated cardiomyopathy during clozapine treatment for a psychosis that did not respond to conventional antipsychotics. The onset of her illness was acute with chest pain. She subsequently developed shortness of breath and oedema of the face and legs. The cardiomyopathy appeared to be partially reversible after the clozapine was halted. Cardiomyopathy during the use of clozapine is rarely described in the literature, although myocarditis is a known complication. The cause of cardiomyopathy during the use of clozapine is not known. Myocarditis might evolve into cardiomyopathy. There are indications that myocarditis is caused by an allergic reaction to clozapine. It is advised that clozapine treatment should only be initiated under the close supervision of a psychiatrist, and that during the use of clozapine one should be alert to the risk of cardiac complications.

TGF-beta1 gene polymorphisms in patients with end-stage heart failure

BACKGROUND

The regulatory cytokine transforming growth factor (TGF)-beta1 is thought to play a role in atherosclerotic heart disease as well as in idiopathic cardiomyopathy. The production of TGF-beta1 is genetically controlled as polymorphisms in the signaling sequence of the TGF-beta1 gene leucine(10)-->proline and arginine(25)-->proline are involved in the regulation of the protein production level. We investigated whether these polymorphisms are associated with end-stage heart failure caused by dilated cardiomyopathy (CMP) or ischemic heart disease (IHD).

METHODS

We determined polymorphisms using sequence specific oligonucleotide probing (SSOP) in genomic DNA samples from heart transplant recipients (n = 253) and controls (n = 94). Indications for transplantation were dilated CMP (n = 109) and IHD (n = 144).

RESULTS

We found a difference in TGF-beta1 codon 10 genotype distribution among patients with IHD, dilated CMP, and controls (p = 0.034; chi(2) test). Patients with dilated CMP differed from patients with IHD (p = 0.044) and healthy controls (0.017). The genotype distribution between patients with IHD and controls was comparable. For codon 25, we found no difference in genotype distribution.

CONCLUSIONS

The Leu(10)-->Pro (codon 10) polymorphism in the TGF-beta1 gene is associated with end-stage heart failure caused by dilated CMP and not with IHD. This observation suggests that TGF-beta1 is involved in the pathogenesis of CMP.

Beneficial effect of carvedilol on heart rate response to exercise in digitalised patients with heart failure in atrial fibrillation due to idiopathic dilated cardiomyopathy

Fourteen digitalised patients diagnosed with heart failure (NYHA Functional class II) with idiopathic dilated cardiomyopathy in chronic established atrial fibrillation were administered carvedilol in addition to their anti-heart failure medications in an attempt to improve their heart rate control. Fourteen matched patients who did not receive carvedilol acted as control subjects. Patients treated with carvedilol showed significantly reduced resting heart rates (10-36%), maximal heart rates on exercise (5-20%) and an increased exercise time (2-30%) on treadmill stress tests (all P=0.001). Ventricular ectopic activity was also diminished. This was associated with symptomatic improvement in effort intolerance and palpitations. NYHA functional class, left ventricular dimensions and ejection fractions did not improve during the study period of 3 months. Thus, addition of carvedilol to digoxin had a beneficial effect on exercise tolerance in patients with idiopathic dilated cardiomyopathy in atrial fibrillation by virtue of an improved heart rate control both at rest and on exercise. Carvedilol was well tolerated despite impaired myocardial function.

Left ventricular and biventricular pacing in congestive heart failure

Dual-chamber pacing improved hemodynamics acutely in a subset of patients with left ventricular (LV) dysfunction but conveyed no long-term symptomatic benefit in most. More recently, LV pacing and biventricular (multisite) pacing have been used to improve systolic contractility by altering the electrical and mechanical ventricular activation sequence in patients with severe congestive heart failure (CHF) and intraventricular conduction delay or left bundle branch block (LBBB). Intraventricular conduction delay and LBBB cause dyssynchronous right ventricular and LV contraction and worsen LV dysfunction in cardiomyopathies. Both LV and biventricular cardiac pacing are thought to improve cardiac function in this situation by effecting a more coordinated and efficient ventricular contraction. Short-term hemodynamic studies have shown improvement in LV systolic function, which seems more pronounced with monoventricular LV pacing than with biventricular pacing. Recent clinical studies in limited numbers of patients suggest long-term clinical benefit of biventricular pacing in patients with severe CHF symptoms. Continuing and future studies will demonstrate whether and in which patients LV and biventricular pacing are permanently effective and equivalent and which pacing site within the LV produces the most beneficial hemodynamic results.

Sympathetic and reflex abnormalities in heart failure secondary to ischaemic or idiopathic dilated cardiomyopathy

Congestive heart failure (CHF) is characterized by a sympathetic activation and a baroreflex impairment whose degree is directly related to the clinical severity of the disease. However, whether these abnormalities vary according to the ischaemic or idiopathic dilated nature of the CHF state has not been conclusively documented. In patients with a clinically stable, chronic CHF state in New York Heart Association functional class II and III, due either to ischaemic heart disease (IHD; n=22, age 60.3+/-2.4 years, means+/-S.E.M.) or to idiopathic dilated cardiomyopathy (IDC; n=20, age 58.9+/-2.8 years), and in 30 age-matched controls, we measured arterial blood pressure (using a Finapres device), heart rate (by electrocardiogram) and postganglionic muscle sympathetic nerve traffic (by microneurography) at rest and during baroreceptor manipulation induced by the vasoactive drug-infusion technique. Blood pressure values were not significantly different in CHF patients and controls. Compared with controls, heart rate was similarly increased and left ventricular ejection fraction (by echocardiography) similarly reduced in CHF patients with IHD or IDC. Muscle sympathetic nerve traffic was significantly greater in CHF patients than in controls, and did not differ between patients with IHD or IDC (67.3+/-4.2 and 67.8+/-3.8 bursts/100 heart beats respectively). This was also the case for the degree of baroreflex impairment. These data show that CHF states due to IHD or to IDC are characterized by a similar degree of peripheral sympathetic activation and by a similar impairment of the baroreflex function. Thus the neuroadrenergic and reflex abnormalities characterizing CHF are independent of its aetiology.

[Only for limited indications. Biventricular pacemaker improves severe heart failure]

In patients with congestive heart disease in whom left ventricular dilatation is associated with severely disordered contraction due to delayed ventricular conduction, a new form of treatment not requiring drugs is currently becoming established--biventricular pacing. Via an implanted electrode, biventricular stimulation accelerates conduction in the left ventricle and resynchronizes its contraction. Patients being considered for such therapy must have stable stage III disease (NYHA classification) under optimal medication, and a left bundle branch block with a QRS of at least 150 ms. Definitive recommendations with regard to indications will be possible only when current randomized mortality studies have been concluded.

Randomized, placebo-controlled study for immunosuppressive treatment of inflammatory dilated cardiomyopathy: two-year follow-up results

BACKGROUND

Previous studies have shown disappointing results for immunosuppressive treatment in patients with dilated cardiomyopathy. Therefore, we studied the effectiveness of such therapy in patients with HLA upregulation on biopsy.

METHODS AND RESULTS

Of 202 patients with dilated cardiomyopathy, 84 patients with increased HLA expression were randomized to receive either immunosuppression or placebo for 3 months; they were then followed for 2 years. After 2 years, there were no significant differences in the primary end point (a composite of death, heart transplantation, and hospital readmission) between the 2 study groups (22.8% for the immunosuppression group and 20.5% for the placebo). The secondary efficacy end point included changes in ejection fraction, end-diastolic diameter, end-diastolic volume, end-systolic volume and NYHA class; left ventricular ejection fraction increased significantly in the immunosuppression group compared with the placebo group (95% CI, 4.20 to 13.12; P<0.001) after 3 months of follow-up. The early favorable effects of immunosuppressive therapy on left ventricular volume, left ventricular diastolic dimension, and New York Heart Association class were also present. This improvement was maintained in the immunosuppression group at 2 years (ejection fraction: 95% CI, 6.94 to 19.04; P<0.001). In addition, on the basis of the protocol-specified definition of improvement, 71.8% patients in the immunosuppression group versus 20.9% patients in the placebo group met the criteria of improvement after 3 months (P<0.001). At the end of the follow-up period, 71.4% patients from the immunosuppression group versus 30.8% patients from the placebo group were improved (P=0.001).

CONCLUSIONS

These data demonstrate a long-term benefit of immunosuppressive therapy in patients with dilated cardiomyopathy and HLA upregulation on biopsy specimens. Thus, restoration of immunosuppressive therapy for such patients should be considered.

Combined spinal-epidural anesthesia for Cesarean section in a patient with peripartum dilated cardiomyopathy

PURPOSE

To report a case of peripartum dilated cardiomyopathy associated with morbid obesity and possible difficult airway presenting for elective Cesarean section, which was successfully managed with combined spinal-epidural anesthesia.

CLINICAL FEATURES

A morbidly obese parturient with a potentially difficult airway, suffering from idiopathic peripartum cardiomyopathy (ejection fraction 20%), was scheduled for an elective Cesarean section. A combined spinal epidural anesthesia was performed and 6 mg of bupivacaine were injected into the subarachnoid space. This was supplemented after 60 min with 25 mg of bupivacaine injected epidurally. The patient's hemodynamic status was monitored with direct intra-arterial blood pressure and central venous pressure measurements. The patient's perioperative course was uneventful.

CONCLUSION

In patients suffering from peripartum cardiomyopathy, undergoing Cesarean section, combined spinal-epidural anesthesia may be an acceptable anesthetic alternative.

Comparison of T-wave alternans and QT interval dispersion to predict ventricular tachyarrhythmia in patients with dilated cardiomyopathy and without antiarrhythmic drugs: a prospective study

Microvolt T-wave alternans (TWA) and QT interval dispersion (QTD), which reflect temporal and spatial repolarization abnormalities, respectively, have been proposed as useful indices to identify patients at risk for ventricular tachyarrhythmias (VTs). The purpose of this study was to clarify which repolarization abnormality marker is more useful in predicting arrhythmic events in patients with dilated cardiomyopathy (DCM). Forty-two consecutive nonischemic DCM patients underwent the assessment of TWA and QTD. Patients undergoing antiarrhythmic pharmacotherapy, except beta-blockers and those with irregular basic rhythms, were excluded from entry. Eight patients were also excluded because of indeterminate test results. Therefore, 34 DCM patients were prospectively assessed. The end point of the study was the documentation of VT defined as > or = 5 consecutive ectopic beats during the follow-up period. TWA and QTD (> or = 65 msec) were positive in 24 (80%) and 11 (37%) of 30 patients with available follow-up data, respectively. There was no relationship between TWA and QTD. During a follow-up of 13+/-11 months, VTs occurred in 13 patients (43%). In Cox regression analysis, TWA was a significant risk stratifier (p=0.02), whereas QTD was not. The sensitivity, specificity, and positive and negative predictive values of TWA in predicting VTs were 100%, 35%, 54%, and 100%, respectively. TWA could be a useful noninvasive index to identify patients at risk for VTs in the setting of DCM. This study may suggest that temporal repolarization abnormality is associated more with arrhythmogenesis than with spatial repolarization abnormality in DCM patients.