PubMed Health⌕ Search

Biomedical subjects

R C Starling

Publications and source records attributed to R C Starling.

At least 37 records · Page 2Linked to original sources
PubMed2001

Partial left ventriculectomy for dilated cardiomyopathy: is this an alternative to transplantation?

OBJECTIVE: To determine the late effectiveness of partial left ventriculectomy and risk factors for failure. METHODS: Between May 1996 and December 1998, partial left ventriculectomy and concomitant mitral valve surgery were performed in 62 patients (95% transplant candidates) with a mean age of 54 years (range 17-72 years). All patients were in New York Heart Association functional class III (38%) or IV (62%) because of idiopathic dilated cardiomyopathy (59 patients) or ischemic, valvular, or familial cardiomyopathy (1 patient each). Outcomes considered for multivariable analysis included implantation of left ventricular assist device, return to class IV heart failure, relisting for transplantation, and death. RESULTS: Partial left ventriculectomy reduced the left ventricular end-diastolic diameter immediately preoperatively to immediately postoperatively (from 8.4 +/- 1.1 cm to 5.92 +/- 0.8 cm; P =.01), reduced the left ventricular end-diastolic volume index (from 133 +/- 48.6 mL to 64.1 +/- 26 mL; P <.0001), and increased the left ventricular ejection fraction (from 16 +/- 7.6 to 31.5 +/- 10.9; P <.0001). Survival was 80% and 60% at 1 and 3 years after surgery and freedom from failure was 49% and 26%, respectively. Increased systolic pulmonary artery pressure, decreased maximum exercise oxygen consumption, and increased left atrial pressure were associated with failure and/or death. The degree of preoperative mitral regurgitation did not correlate with clinical outcome. CONCLUSIONS: Early and late failures preclude the widespread use of partial left ventriculectomy. However, in view of its sometimes beneficial effect, use in situations that do not allow for transplantation or as a biologic bridge to transplantation may be appropriate.

Adolescent↗
PubMed2000

The impact of HLA sensitization and donor cause of death in heart transplantation.

Current expansion of the recipient population and increased utilization of left ventricular assist devices as a bridge-to-transplantation have resulted in HLA sensitization becoming an increasingly important clinical problem in cardiac transplantation. We evaluated the impact of HLA sensitization and donor cause of death on survival in 500 cardiac transplant recipients. Donor cause of death was grouped into two categories, trauma and nontrauma. Panel reactive antibodies at the time of transplant were assayed and used as a marker for sensitization if more than 10%. Sensitized recipients had a poorer 1-year survival than those not sensitized (76 vs. 89%, respectively, P=0.2). Donor cause of death had an overall significant impact on survival with 1-year survival for recipients of trauma organs of 92 and 82% for recipients of nontrauma hearts (P=0.02). Trauma hearts transplanted into sensitized recipients yielded a survival of 93% at 1 year whereas if nontrauma donor hearts were transplanted into these recipients, survival was only 52% at 1 year, P<0.001. These intriguing results suggest that graft survival in HLA-sensitized recipients could be significantly improved through the use of hearts from trauma death donors.

Adolescent↗
PubMed2000

The impact of routine mycophenolate mofetil drug monitoring on the treatment of cardiac allograft rejection.

INTRODUCTION: Mycophenolate mofetil (MMF) is a unique immunosupressive agent that has been shown to be efficacious in the treatment of cardiac allograft rejection. The utility of therapeutic drug monitoring on rejection prophylaxis and treatment is inconclusive. This study was undertaken to evaluate the incidence of rejection in relation to MMF trough level following heart transplantation. METHODS: Between May 1998 and February 1999, we retrospectively analyzed the clinical outcome of 215 heart transplant patients who had routine monitoring of MMF trough level at the time of scheduled endomyocardial biopsy. Patients were divided into three groups according to the time interval post transplant, and were evaluated in relation to the MMF trough level. Group I, 104 patients within 6 months of transplant; Group II, 90 patients, 6-12 months post transplant; and Group III, 71 patients beyond one year of transplant. Fifty patients had samples in more than one group. Rejection was defined as Grade > or = 3A based on ISHLT criteria. Mean follow-up period was 179+/-52 days. RESULTS: A significantly decreased incidence of rejection was noted in the samples with MMF trough level > or = mg/l compared to those with less than 2 mg/l inpatients evaluated within the first year of transplant (Group I: 8.8% vs. 14.9%, Group II: 4.2% vs. 11.3%, both P=0.05). In the presence of therapeutic cyclosporine (CSA) or tacrolimus (FK) blood levels, the incidence of rejection decreased significantly when MMF trough level was > or = 2 mg/l compared to samples with MMF trough level <2 mg/l (3.6% vs. 14.4%, P=0.005). No significant difference was noted in the presence of subtherapeutic CSA or FK levels (15.4% vs. 13.9%, P=NS). CONCLUSIONS: Monitoring of MMF trough levels may play a role in the management of cardiac transplant recipients during the first year post transplant.

Adult↗
PubMed2000

Results of partial left ventriculectomy for dilated cardiomyopathy: hemodynamic, clinical and echocardiographic observations.

OBJECTIVES: The study was done to prospectively measure the echocardiographic, hemodynamic and clinical outcomes after partial left ventriculectomy (PLV). BACKGROUND: Although PLV can improve symptoms of advanced heart failure, immediate postoperative echocardiographic findings remain abnormal. METHODS: Fifty-nine patients with cardiomyopathy and advanced heart failure underwent PLV and concomitant mitral valve surgery between May 1996 and December 1997. Thirty-nine percent were on inotropic therapy. All were New York Heart Association (NYHA) functional class III or IV. Mechanical circulatory support (LVAD) and transplant were provided for rescue therapy when hemodynamic compromise occurred. Patients were followed for a mean of 405+/-168 days, and clinical, echocardiographic and hemodynamic measures were obtained preoperatively, immediately postoperatively, and at 3 and 12 months prospectively. RESULTS: Comparing preoperative and 12-month postoperative values in event-free survivors, we found: NYHA functional class improved from 3.6 to 2.1, p < 0.0001; peak oxygen consumption increased from 10.8 to 16.0 ml/kg/min, p < 0.0001; LV ejection fraction increased from 13+/-6.0% to 24+/-6.9%, p < 0.0001; LV end diastolic diameter decreased from 8.2+/-1.03 to 6.2+/-0.64 cm, p < 0.0001, and volume was reduced from 167+/-60 to 105+/-38 ml/m2, p = 0.02. Central hemodynamics did not normalize after surgery. CONCLUSIONS: Partial left ventriculectomy can provide structural remodeling of the heart that may result in temporary improvement in clinical compensation. However, perioperative failures and the return of heart failure limit the propriety of this procedure.

Aged↗
PubMed2000

The clinical significance of flow cytometry crossmatching in heart transplantation.

OBJECTIVE: Flow cytometry crossmatching (FCXM) is more sensitive than the cytotoxic crossmatch in identifying preformed antibodies to donor alloantigens, but its clinical importance is controversial. The objective of this study was to determine the association of a FCXM with survival and incidence of vascular rejection in cardiac transplant recipients with a negative cytotoxic crossmatch. METHODS: Between 1993 and 1998, 357 heart transplant recipients with a negative T cell cytotoxic crossmatch were studied by three-color FCXM to quantitate anti-donor IgG reactions against B and T lymphocytes. Reactions positive against both were consistent with human leukocyte antigen (HLA) Class I reactivity, and those against B cells only were considered to be against HLA Class II antigens. Endpoints were episodes of vascular rejection, death from acute and chronic rejection and overall survival. RESULTS: Fifty patients were FCXM for Class I-positive, 144 for Class II-positive, and 163 were negative. At 1 month, freedom from vascular rejection was 64% in Class I patients, but 90% and 96% in Class II or negative crossmatch patients (P<0.0001). Survival of the negative crossmatch group was higher than either Class I or II groups (94%, 74% and 76%, respectively, at 3 years; P<0.0001). Death from acute rejection was 3% and 2% at 3 years in negative or Class II-positive patients, but 19% in Class I patients (P<0.0001). Death from chronic rejection occurred only in Class II patients (P=0.002). CONCLUSIONS: Despite a negative T-cell cytotoxic crossmatch, a positive flow cytometry crossmatch correlates with important clinical events after heart transplantation.

Adolescent↗
PubMed2000

Efficacy of tacrolimus in patients with steroid-resistant cardiac allograft cellular rejection.

BACKGROUND: Tacrolimus is an immunosuppressive agent that is gaining widespread use in solid organ transplantation. This study was undertaken to evaluate the efficacy of tacrolimus in treating steroid-resistant cellular myocardial rejection. METHODS: We retrospectively analyzed the incidence of rejection and clinical outcome of 21 heart transplant recipients who were electively converted from cyclosporine to tacrolimus for recurrent episodes of steroid-resistant cellular rejection. These were compared to a historic group of 6 hemodynamically stable patients who were treated electively with Orthoclone OKT3 (Muromonab/CD3) for recurrent rejection. RESULTS: Eighty five percent (56/66) of the episodes of rejection occurred within the first 3 months after heart transplantation. Tacrolimus was started 2. 4 +/- 2.0 months post-transplant, and the mean follow-up duration on tacrolimus was 11.0 +/- 7.0 months. After conversion, a significant decline was noted in both the number of episodes of acute rejection per patient (3.14 +/- 0.85-0.57 +/- 0.87, p < 0.0001), and the incidence of acute rejection per 100 patient-days (6.39 +/- 3.96-0. 25 +/- 0.47, p < 0.0001). In comparison, OKT3 was started 5.25 +/- 9. 20 months post-transplant. Similarly, there was a significant decrease in the incidence of acute rejection per 100 patient-days (8. 69 +/- 5.65-0.20 +/- 0.23, p < 0.0001). The average hospital charges per patient for the OKT3-treated group was $33,339 +/- $10,511. There was no significant difference in the actuarial 1-year survival between the tacrolimus and OKT3-treated groups (93% vs 80%, p = 0.5). CONCLUSIONS: Outpatient conversion to tacrolimus is safe, well tolerated, and an effective therapeutic strategy for the treatment of steroid-resistant cellular rejection in heart transplant recipients. It is more cost-effective than OKT3 in the hemodynamically stable patient and outcomes are similar.

Adult↗
PubMed2000

Fluorescence spectroscopy of endomyocardial tissue post-human heart transplantation: does it correlate with histopathology?

BACKGROUND: A significant correlation between autofluorescence spectroscopy and heart allograft rejection has been described in the rat heterotropic allograft model. However, the use of this technique in human heart transplants has not been validate. METHODS: We obtained fluorescence and reflectance spectra on 37 human endomyocardial biopsy specimens and correlated the spectra with International Society Heart and Lung Transplantation grade for histologic rejection. RESULTS: Using different excitation wavelengths (ultraviolet, lambda = 337 nm; blue, lambda = 440 nm, and green, lambda = 486 nm), we found no significant difference in the fluorescence spectra among the different grades of rejection. CONCLUSIONS: Fluorescence spectroscopy is not a sensitive method for detecting rejection in human heart transplant recipients.

Adult↗
PubMed2000

Left ventricular reduction surgery with mitral valve repair.

The echocardiographic changes and functional outcome from mitral valve repair, combined with partial left ventriculectomy (PLV), the Batista procedure, were investigated. From May 1996 to August 1997 the operation was performed on 57 patients, primarily (95%) transplant candidates with idiopathic dilated cardiomyopathy. All had been Class IV (36.8% had improved to Class III by the time of surgery) on medical therapy, including 40% hospitalized on inotropes and 3 patients on intra-aortic balloon pumps. The mean cardiac index was 2.1+/-0.6 L/min/m2, with a wedge pressure of 24+/-8 mm Hg, and norepinephrine levels of 855+/-500 pg/mL (normal 80-526 pg/mL). There were 2 in-hospital mortalities (3.5%). At 3 months there were significant persistent changes in LV end-diastolic diameter (8.1+/-1.0 cm-6.3+/-0.9 cm) and ejection fraction (13.6+/-6%-23+/-7.7%). Subjective improvement included a mean change in NYHA functional class from 3.7 to 2.2, and objective changes included improvement in peak oxygen consumption from 10.6+/-4 mL/kg/min to 15.4+/-4.5 mL/kg/min. Actuarial survival at 1 year was 82.1%; and freedom from death, relisting for transplantation, and need for LVAD support was 58%. The earliest "learning curve" experience with this relatively unstudied operation warrants careful investigation. Many questions remain to be answered, but many patients have demonstrated early subjective and objective improvement.

Cardiac Surgical Procedures↗
PubMed2000

Clinical experience with long-term use of implantable left ventricular assist devices: indications, implantation, and outcomes.

We describe our clinical experience with 205 implantable left ventricular assist devices at the Cleveland Clinic between December 1991 and January 2000, along with manufacturers' data submitted to the Food and Drug Administration. In patients with end-stage cardiac failure who are suitable candidates for transplantation, these devices serve as excellent bridges to transplantation. Recent modifications have increased pump reliability and reduced thromboembolic rates. The vented electric HeartMate (Thermocardiosystems Inc, Woburn, MA) and the Novacor (Baxter-Novacor, Oakland, CA) left ventricular assist systems allow patients to be discharged from the hospital while awaiting a donor heart. Experience with long-term support is providing insights into permanent implantation of these devices as destination therapy. Although infection remains a major impediment to long-term support, patient-pump interactions leading to changes in the coagulation and immune systems are being recognized, and these interactions may have important implications with respect to thromboembolism, infection, and sensitization to human leukocyte antigens (HLAs). Better understanding of these factors may eventually lead to the development of permanently implantable pumps as an alternative to transplantation.

Assisted Circulation↗
PubMed2000

Dissociation between ACE activity and autonomic response to ACE inhibition in patients with heart failure.

BACKGROUND: Administration of angiotensin-converting enzyme (ACE) inhibitors to patients with congestive heart failure has been shown to increase parasympathetic tone as indicated by increases in high-frequency heart rate variability. The mechanism for this effect, including its relation to changes in baroreflex activity, blood pressure variability, and suppression of ACE activity, remains undefined. This study was designed to test the relation of these variables, which may govern changes in autonomic activity, to the previously described increase in parasympathetic tone. METHODS: Seven patients with heart failure received a 3-hour infusion of the ACE inhibitor enalaprilat. Hemodynamic variables and parameters of heart rate and blood pressure variability, baroreflex gain derived from the interaction of heart rate and blood pressure variability, and serum ACE activity were measured during and after the infusion. Measures of heart rate and blood pressure variability were also compared against a historic control group. RESULTS: Serum ACE activity was significantly suppressed throughout and after enalaprilat infusion. Hemodynamic measures did not change other than a small decline in right atrial and pulmonary capillary wedge pressures. Parasympathetic tone showed an initial significant increase with a peak at 2 hours but then declined below baseline 8 hours after initiation of enalaprilat infusion. Sympathetically influenced low-frequency heart rate variability was significantly increased above baseline in the enalaprilat treatment group 8 hours after initiation of the infusion. Baroreflex gain showed a significant trend to an increase with the maximum value coinciding with the peak in parasympathetic tone. There was no change in blood pressure variability in the enalaprilat group and no change in baroreflex gain, heart rate variability, or blood pressure variability in the control group. CONCLUSIONS: Parasympathetic tone and baroreflex gain increased with parenteral administration of an ACE inhibitor but subsequently decreased below baseline values despite continued suppression of serum ACE activity. The dissociation between ACE suppression and autonomic response to ACE inhibition indicates that enzyme systems not reflected by plasma ACE activity or independent from the classic pathways of angiotensin formation contribute to the regulation of the autonomic response to ACE inhibition in patients with heart failure. The absence of significant change in hemodynamic variables or in blood pressure variability indicates that these autonomic changes are not an indirect reflex response to ACE inhibitor-induced vasodilation or hemodynamic baroreceptor stimulation.

Adult↗
PubMed2000

Long-term medical complications of heart transplantation: information for the primary care physician.

As heart transplantation becomes much more common primary care physicians will play a key role in preventing, detecting, and treating the short-term and long-term complications of this procedure. These complications include chiefly graft rejection and accelerated coronary artery disease, but also dyslipidemia, hypertension, diabetes mellitus, kidney failure, gout, osteoporosis, and malignancy.

Antibiotic Prophylaxis↗
PubMed1999

Preoperative risk factors for right ventricular failure after implantable left ventricular assist device insertion.

BACKGROUND: Implantable left ventricular assist device (LVAD) insertion complicated by early right ventricular (RV) failure has a poor prognosis and is generally unpredictable. METHODS: To determine preoperative risk factors for perioperative RV failure after LVAD insertion, patient characteristics and preoperative hemodynamics were analyzed in 100 patients with the HeartMate LVAD (Thermo Cardiosystems, Inc, Woburn, MA) at the Cleveland Clinic. RESULTS: RV assist device support was required for 11 patients (RVAD group). RVAD use was significantly higher in younger patients, female patients, smaller patients, and myocarditis patients. There was no significant difference in the cardiac index, RV ejection fraction, or right atrial pressure between the two groups preoperatively. The preoperative mean pulmonary arterial pressure (PAP) and RV stroke work index (RV SWI) were significantly lower in the RVAD group (p = 0.015 and p = 0.011, respectively). Survival to transplant was poor in the RVAD group (27%) and was 83% in the no-RVAD group. CONCLUSIONS: The need for perioperative RVAD support was low, only 11%. Preoperative low PAP and low RV SWI were significant risk factors for RVAD use.

Adult↗
PubMed1999

Oral steroid pulse without taper for the treatment of asymptomatic moderate cardiac allograft rejection.

BACKGROUND: The most frequently administered treatment for asymptomatic ISHLT Grade 3A cardiac allograft rejection is intravenous steroids or oral steroid pulse with a taper. This study analyzes the efficacy of 3-day 100-mg course of prednisone without a tapered regimen for the treatment of asymptomatic moderate cardiac allograft rejection. METHODS: All new episodes of asymptomatic ISHLT Grade 3A rejections were treated with oral steroid pulse without taper, consisting of 100 mg of prednisone for 3 consecutive days followed by resuming the pre-rejection steroid dose on the fourth day. We retrospectively reviewed the histologic response of all treated episodes among all cardiac transplant recipients transplanted between January 1995 through December 1997 who were treated with triple therapy consisting of cyclosporine, azathioprine and steroids. Patients receiving additional or alternative immunosuppressives were excluded from the study. The treated episodes were analyzed as responders if the follow-up biopsy were Grade 0, 1A, 1B, or 2; treatment was counted as non-responders if the follow-up biopsy showed Grade 3A or higher. RESULTS: Of 230 cardiac transplant recipients, 100 patients received a 3-day 100 mg course of prednisone without taper for 174 new episodes of asymptomatic ISHLT Grade 3A rejection. The overall response rate was 75% (130/174 rejection episodes). A significant difference in the response rate was observed depending on the number of days post transplant. A comparison of the success rates among rejections which occurred > 90 days post transplant versus < 30 days revealed responses to be 88% versus 70% (p = 0.02); for rejections treated > 60 days post transplant versus < 30 days showed success rates of 84% versus 70% (p = 0.04). The mean age of the recipient revealed a trend to be lower among the non-responder group (49+/-12 years versus 53+/-9 years, p = 0.07). Having left ventricular assist device as a bridge to transplant did not significantly affect the treatment outcome. The response rates were 69% for the patients who required the assist device versus 77% for those not bridged (p = ns). There was no significant difference in the gender or the baseline immunosuppressive doses between the responders and non-responders. The cost of a 3-day outpatient, visiting nurse supervised intravenous steroid therapy versus 3 days of oral prednisone was $861 vs $6.88. CONCLUSION: Oral steroid pulse without taper is an effective and economical way to treat asymptomatic moderate grade cardiac allograft rejection. A 3-day course of 100 mg of prednisone without taper should be considered as first line of therapy for clinically stable form of moderate cardiac allograft rejection occurring > 60 days post transplant.

Administration, Oral↗
PubMed1999

Partial left ventriculectomy: sunrise or sunset?

Partial left ventriculectomy (PLV) was proposed as an alternative to cardiac transplantation for patients with advanced heart failure. Patients with dilated cardiomyopathy that were considered eligible candidates for cardiac transplantation were offered the option of surgical ventriculectomy or to continue waiting for a donor organ. Sixty-two patients underwent PLV between May 1996 and December 1998, mean age 54 years, 47 males, mean ejection fraction 13.5%, mean peak oxygen consumption 10.8 ml/kg/min, 39% NYHA class III and 61% NYHA IV. Perioperative mortality 3.2%, 10/62 (16%) required implant of a left ventricular assist device (LVAD) due to shock, most in the early post-operative period. Survival at 1 and 2 years was 78% and 68%. Event free survival (freedom from death, LVAD, or return of NYHA class IV failure) was 50% and 37% at 1 and 2 years. Event free survivors experienced improvement in NYHA class (3.7 to 2.2) and increased oxygen consumption (11.7 to 16.0 ml/kg/min). Based on these data PLV has a significant early failure rate and a 2 year event free survival rate of only 37%. PLV does not yield outcomes equivalent to cardiac transplantation based on current selection criteria and requires further investigation to determine its role in the treatment of advanced heart failure.

Cardiomyopathy, Dilated↗
PubMed1998

Development of transplantation vasculopathy and progression of donor-transmitted atherosclerosis: comparison by serial intravascular ultrasound imaging.

BACKGROUND: Transplant coronary artery disease is a combination of atherosclerosis transmitted from the donor and new lesions of allograft vasculopathy. We sought to determine the morphological characteristics of allograft vasculopathy and differentiate it from donor-transmitted atherosclerosis with serial intravascular ultrasound. METHODS AND RESULTS: Intravascular ultrasound examination was performed in 93 patients at 27.2+/-15.0 and 369. 7+/-23.9 days after transplantation. The maximally and minimally diseased sites were selected in each segment as defined by Coronary Artery Surgery Study classification. For each matched site, maximal plaque thickness was measured. Lesions (maximum plaque thickness >/=0.5 mm) present at baseline examination were defined as donor lesions. On follow-up, lesions that developed at previously normal sites were defined as de novo lesions. The distribution and severity of donor and de novo lesions were similar in proximal, mid, and distal segments. The de novo lesions were less focal (43% vs 74%) and more circumferential (69% vs 45%) compared with the donor lesions, but there was significant morphological heterogeneity. Similar numbers of patients with and those without donor lesions developed de novo lesions. Moreover, progression of donor lesions was not associated with the presence or absence of de novo lesions. CONCLUSIONS: Differentiation between early allograft vasculopathy from conventional atherosclerosis by distribution and morphology of lesions alone is difficult. Serial intravascular ultrasound imaging with early baseline examination is necessary to make this distinction. This distinction is important because the progression of donor lesions and the development of de novo lesions are independent of each other.

Adolescent↗
PubMed1998

One hundred patients with the HeartMate left ventricular assist device: evolving concepts and technology.

BACKGROUND: Implantable left ventricular assist devices are common as a bridge to transplantation but are just reaching their goal as an alternative to transplantation. METHODS: From December 1991 until December 1996, 97 left ventricular assist devices were implanted as a bridge to transplantation, one as an alternative to transplantation, and two as a bridge to recovery. Included were 64 pneumatic devices and 36 electric devices. Most patients (69%) had ischemic cardiomyopathy and most (53%) had had previous cardiac surgery. Preoperative circulatory support (extracorporeal membrane oxygenation) was used in 25. RESULTS: Perioperative insertion of a right ventricular assist device was unusual (11%). The mean duration of support with a left ventricular assist device (bridge to transplantation) was 70 +/- 41 days (up to 206 days). Survival to transplantation was 76%. Cause of death included multiple organ failure (n = 13), perioperative stroke (n = 5), device failure (n = 5), and controller disconnect (n = 1). Significant risk factors for death included (1) preoperative need for ventilator or extracorporeal membrane oxygenation, (2) elevated blood urea nitrogen, creatinine, or bilirubin, and (3) low pulmonary artery pressures. Risks after insertion of the left ventricular assist device were reoperation for bleeding, support with a right ventricular assist device, dialysis, or device failure. Catastrophic failure of the device occurred 14 times in 12 patients and was treated by emergency pump exchange in six instances. Only two device-related thromboembolic episodes were detected. Positive blood cultures were found in 59% of patients, driveline infection in 28%, and pump infection in 11%. CONCLUSIONS: The HeartMate device provided excellent hemodynamic support with low device-related thromboembolic events. Infection and reliability of the device contributed to the high cost of therapy. These areas need to be improved for the left ventricular assist device to attain its goal as a viable alternative to transplantation.

Actuarial Analysis↗
PubMed1998

Surgical therapy for dilated cardiomyopathy.

As the next millennium approaches, excitement and promise characterize the future of dilated cardiomyopathy. Until recently, dilated cardiomyopathy was considered an incurable, uniformly fatal chronic disease. Epidemiologic studies have demonstrated that at least a quarter of patients with recent onset of symptoms with cardiomyopathy manifest spontaneous improvement and a sustained favorable prognosis. It is imperative that patients who present with new-onset cardiomyopathy be managed medically and closely followed. Medical treatment remains the foundation of therapy, and certainly the advent of beta-blocker use may herald further benefit beyond that observed with conventional therapy (ACE inhibitors and digoxin). Unless mechanical support is required for hemodynamic instability and end organ failure, patients should be treated medically and observed. As discussed earlier, transient mechanical support as a bridge to recovery should be considered in the appropriate clinical scenario before committing to cardiac transplantation. Patients with established disease who have been followed for extended periods (> 6 months) that have progressive symptoms despite optimal medical therapy should be considered for surgical therapies. Cardiac transplantation is available to only a minority of the diseased population. All newer modalities of surgical unloading therapy theoretically reduce wall stress. Clearly in dilated cardiomyopathy, ventricular performance is reduced; however, individual myocyte contractile function may be intact. Studies of isolated myocytes (which are unloaded) have yielded conflicting data; however, if contractile function is intact and performance is reduced primarily secondary to abnormal loading conditions, surgical unloading therapies should yield benefit. Hence the thesis of Batista that geometric alteration will improve performance assumes intrinsic integrity of the myocyte contractile function. The implication of intrinsic myocyte contractile dysfunction is that surgical remodeling does not yield improved ventricular performance. Although clinicians have learned that selection criteria appear to play a role in predicting beneficial outcomes with cardiomyoplasty and the Batista procedure, clinical techniques to assess the integrity of myocyte function are unsophisticated. Quantifying interstitial fibrosis, assays for the degree of apoptosis, and various immunologic measures currently do not provide the insight necessary to predict outcomes reliably. The future assessment of dilated cardiomyopathy and the decision to consider alternative surgical procedures versus cardiac transplantation will likely be determined by biomolecular studies. At present, these new surgical procedures are promising therapies and potential alternatives to cardiac transplantation. Controlled studies to determine the clinical and survival benefit compared with medical therapy will ultimately be required, after the surgical techniques and patient selection criteria are refined. Randomized, prospective controlled studies assessing LVAD therapy and cardiomyoplasty are in progress.

Cardiac Surgical Procedures↗