The impact of newly diagnosed patent foramen ovale in patients undergoing off-pump coronary artery bypass grafting: case series of eleven patients.

UNLABELLED: The increased use of transesophageal echocardiography (TEE) by anesthesiologists may lead to an increase in the intraoperative detection of previously undiagnosed patent foramen ovale (PFO). The impact of heart manipulation on interatrial shunting through a PFO during off-pump coronary artery bypass graft (CABG) has not been studied. We retrospectively studied 11 patients with PFOs who underwent off-pump CABG. TEE contrast studies and blood gas analyses were performed at baseline, during heart elevation for distal coronary arteries anastomoses, and at the end of the surgery. At baseline, 5 of 11 patients had left-to-right shunting and 2 of 11 had right-to-left shunting. Heart elevation did not result in oxygen desaturation in any patient; however, it caused the disappearance of a right-to-left shunt (n = 1), persistence of this shunt (n = 1), and the development of a new right-to-left shunt (n = 2). Return of the heart to its original position resulted in a return of TEE findings to the baseline state in all patients. This series suggests that off-pump CABG can be performed safely in the majority of patients with PFOs; however, additional investigation is needed to assure that adverse effects do not occur in a subset of patients undergoing off-pump CABG in the presence of a PFO. IMPLICATIONS: This case series suggests that coronary artery bypass graft surgery can be safely performed in most patients with patent foramen ovale without the use of a cardiopulmonary bypass.

Current options for mechanical heart technology.

Heart transplantation remains the treatment of choice for end-stage heart failure despite limited donor availability and allograft durability. Artificial heart technology was initially developed as a replacement for transplantation but the initial experience with these technologies was disappointing. The quest for a total artificial heart has largely been abandoned in favor of ventricular assist devices (VADs). VADs have gained widespread acceptance as bridge to transplant and bridge to recovery therapy. After more than a decade of clinical use, several FDA approved device designs have proved effective in treating patients with various causes of heart failure. This review describes the current, clinically available ventricular replacement and assist devices and defines the adult patient populations in which they are useful. The next generation of these devices will soon become available and their clinical utility will likely shape the future direction of heart failure therapy. Ultimately the concept of a long-term total artificial heart may be revisited.

Intravenous allicin improves pulmonary blood flow after ischemia-reperfusion injury in rats.

BACKGROUND: Allicin is a sulfur-containing compound extracted from garlic, with antiaggregatory, anti- migratory, anti-oxidant and pulmonary vasodilator actions. We hypothesized that allicin might be beneficial in lung ischemia-reperfusion. METHODS: A non-nothermic rat lung ischemia-reperfusion model was established by clamping left pulmonary artery (PA) for 1 hr, followed by reperfusion for 2 hrs by clamping right PA to reflect solely the function of left lung. Groups were control (n=7), allicin 0.1 mg (n=8) and allicin 0.01 mg (n=4). In the beginning of reperfusion allicin/saline were injected. Pulmonary artery pressures (PAP), pulmonary artery flow (PAF), left atrial pressure (LAP) were monitored. At the end of reperfusion period arterial blood gas (ABG) analysis was done. RESULTS: Six of 7 control and 3 of 8 group 2 animals died before completing the experiment. In group 1 all animals completed the experiment (p=0.015 vs control). PAF was significantly increased after 30, 60 and 120 min of reperfusion in group 1 (p=0.0028, 0.0009, 0.0003 respectively vs control) and after 60 and 120 minutes in group 2 (p=0.0453, 0.018 respectively vs control). Pulmonary vascular resistance was lower at 30 min in allicin 0.01 mg group (p=0.0017 vs control). PAP was increased after 60 and 120 min of reperfusion in group 1 (p=0.016, 0.0029 respectively vs control) and after 120 min in group 2 (p=0.0104 vs control). CONCLUSIONS: This study shows that allicin improves postischemic PAF in this model. Allicin needs further investigation of potential utility and mechanism(s) of action.

Multicenter clinical evaluation of the HeartMate vented electric left ventricular assist system in patients awaiting heart transplantation.

BACKGROUND: Despite advances in heart transplantation and mechanical circulatory support, mortality among transplant candidates remains high. Better ways are needed to ensure the survival of transplant candidates both inside and outside the hospital. METHODS: In a prospective, multicenter clinical trial conducted at 24 centers in the United States, 280 transplant candidates (232 men, 48 women; median age, 55 years; range, 11-72 years) unresponsive to inotropic drugs, intra-aortic balloon counterpulsation, or both, were treated with the HeartMate Vented Electric Left Ventricular Assist System (VE LVAS). A cohort of 48 patients (40 men, 8 women; median age, 50 years; range, 21-67 years) not supported with an LVAS served as a historical control group. Outcomes were measured in terms of laboratory data (hemodynamic, hematologic, and biochemical), adverse events, New York Heart Association functional class, and survival. RESULTS: The VE LVAS-treated and non-VE LVAS-treated (control) groups were similar in terms of age, sex, and distribution of patients by diagnosis (ischemic cardiomyopathy, idiopathic cardiomyopathy, and subacute myocardial infarction). VE LVAS support lasted an average of 112 days (range, < 1-691 days), with 54 patients supported for > 180 days. Mean VE LVAS flow (expressed as pump index) throughout support was 2.8 L x min(-1) x m(-2). Median total bilirubin values decreased from 1.2 mg/dL at baseline to 0.7 mg/dL (P =.0001); median creatinine values decreased from 1.5 mg/dL at baseline to 1.1 mg/dL (P =.0001). VE LVAS-related adverse events included bleeding in 31 patients (11%), infection in 113 (40%), neurologic dysfunction in 14 (5%), and thromboembolic events in 17 (6%). A total of 160 (58%) patients were enrolled in a hospital release program. Twenty-nine percent of the VE LVAS-treated patients (82/280) died before receiving a transplant, compared with 67% of controls (32/48) (P <.001). Conversely, 71% of the VE LVAS-treated patients (198/280) survived: 67% (188/280) ultimately received a heart transplant, and 4% (10/280) had the device removed electively. One-year post-transplant survival of VE LVAS-treated patients was significantly better than that of controls (84% [158/188] vs 63% [10/16]; log rank analysis P =.0197). CONCLUSION: The HeartMate VE LVAS provides adequate hemodynamic support, has an acceptably low incidence of adverse effects, and improves survival in heart transplant candidates both inside and outside the hospital. The studies of the HeartMate LVAS (both pneumatic and electric) for Food and Drug Administration approval are the only studies with a valid control group to show a survival benefit for cardiac transplantation.

Left ventricular volume reduction surgery for heart failure: a physiologic perspective.

BACKGROUND: Ventricular volume reduction surgery for idiopathic cardiomyopathy fails to improve cardiac output and is associated with a high incidence of recurrent heart failure. Volume reduction surgery achieved by removing akinetic or dyskinetic myocardium after myocardial infarction appears to be associated with better outcomes. The reasons for the differences in outcomes are not clear. METHODS AND RESULTS: The hemodynamic effect of the major forms of volume reduction surgery were predicted by using a composite model of the left ventricle in which 20% of the myocardium was given properties of either weak but contracting muscle, an akinetic scar, or a dyskinetic scar (aneurysm). The end-systolic and end-diastolic pressure-volume relationships were determined numerically for each simulated operation. Any volume reduction procedure reduced chamber size, shifting end-systolic and end-diastolic pressure-volume relationships leftward. With resection of weak but contracting muscle, the leftward shift was greater for the end-diastolic than for the end-systolic pressure-volume relationship. Conversely, with resection of dyskinetic scar, the leftward shift was greater for end-systolic than for end-diastolic pressure-volume relationships. In contrast, resection of stiff scar shifted the 2 relationships equally. The effect on overall pump function was indexed by the relationship between total ventricular mechanical work and end-diastolic pressure. There was a beneficial effect on this relationship of resecting dyskinetic tissue, an equivocal effect of akinetic scar resection, and a negative effect of removing contracting myocardium. CONCLUSIONS: The effect of volume reduction surgery on overall ventricular pumping characteristics is determined by the differential effects on end-systolic and end-diastolic properties, which in turn are determined by the material properties of the region being removed.

Surgical issues in heart failure: what's new?

Despite major advances in inotropic medications and our understanding of their proper use, surgical management of heart failure is the fastest-growing aspect of cardiovascular surgery. In addition to causing 750,000 deaths annually, myocardial infarctions leave an estimated 60,000 more patients in severe congestive heart failure and several times more individuals with compromised ventricular function. As these patients are offered reparative surgical options, surgeons, anesthesiologists, and cardiologists face physiologic challenges that can be optimally overcome only by modifying treatment strategies to address patients who have failed appropriate medical therapy, including milrinone, vasopressin, and nitric oxide. As our comfort with mechanical support increases, the threshold for embarking on these lines of treatment will be altered. Innovative devices have been created to meet this clinical need, but they must provide adequate quality of life to create sustainable value and health for society.

Novel technique to repair type A acute aortic dissection in patients with a left ventricular assist device.

Acute type A aortic dissection is an uncommon complication with left ventricular assist device insertion, but is often fatal even if successfully repaired with conventional techniques including aortic valve repair. Residual aortic insufficiency is common because this valve is now subjected to systolic pressure. We present a novel technique for the repair of type A acute aortic dissection in patients with a left ventricular assist device with no chance of residual aortic insufficiency.

Normalized diastolic properties after left ventricular assist result from reverse remodeling of chamber geometry.

BACKGROUND: Normalization of diastolic properties after left ventricular (LV) assist may result from a change in myocardial material properties, chamber size, or both. This study tested the hypothesis that reported normalization of LV diastolic properties is primarily due to remodeling of chamber geometry. METHODS AND RESULTS: Hearts were obtained at transplantation from 8 patients with dilated cardiomyopathy (DCM), 6 patients with DCM plus 33+/-5 days of LV assist, and 3 patients with no evidence of heart failure. LV assist normalized passive pressure-volume curves. Chamber dimensions decreased without a change in the ratio of radius to wall thickness. Midwall stress-stretch relations predicted from pressure-volume and dimension data were not different for DCM and LV assist hearts. Passive stress-stretch relations were measured in endocardial trabeculae and were not different for DCM and LV assist hearts. Myocyte size and collagen area fraction were unchanged at this brief duration of support. CONCLUSIONS: These findings are all consistent with the hypothesis that early normalization of diastolic properties after LV assist device support results from remodeling of chamber geometry, not from changes in tissue stiffness. These data emphasize the importance of geometry to ventricular mechanics and demonstrate that reduction of heart size does not necessarily produce a reduction in wall stress.

Discrepancy between claimed field flux density of some commercially available magnets and actual gaussmeter measurements.

CONTEXT: Magnets are widely used by the public in medical applications. OBJECTIVES: To determine whether the field flux density, a measurement of magnetic dosage, provided by over-the-counter magnet manufacturers is accurate. DESIGN: Five magnets were tested for field flux density, and measurements were compared with information provided by manufacturers. RESULTS: Magnets studied showed actual field flux density measurements that were significantly lower than the values claimed by suppliers. CONCLUSIONS: Over-the-counter magnet suppliers are not providing reliable information; therefore, clinical replication of published reports is difficult.

Patient evaluation of the hotel function of hospitals.

BACKGROUND: A means of measuring patient satisfaction is essential in the effort to improve the quality of health care delivered in our nation's hospitals. Accurate feedback allows employers to better meet patients' needs and allows hospital administrators to improve service delivery. Patients are empowered by having a voice in the manner in which their health care is delivered. Moreover, improving the efficiency of the health care delivery system decreases health care costs. Hospital comparisons can be made readily available to a large audience through the Internet, resulting in empowerment of the patient and a universal improvement in hospital care. This is the first multi-institutional analysis of patient satisfaction among New York City and northern New Jersey area tertiary care hospitals. In this study, we evaluated the patient-assessed hotel function of hospitals in a single geographic region to determine whether clinically and statistically significant differences would be revealed that could provide beneficial information to stakeholders in the healthcare system. METHODS: Patients (n = 261) who had spent a night during the past year in one of eleven hospitals within 60 miles of New York City were chosen at random from doctors' waiting rooms. On average, 24 patients from each hospital were surveyed. They were asked to complete a questionnaire that rated the various departments in the hospital on qualities such as courtesy, promptness, and cleanliness. The questionnaire also rated important characteristics of the patient experience, such as the ease of parking and the taste of the food. Each item on the survey was coded on a scale of 1 to 10 with 10 being the most positive response. The 26 specific questions were divided into 14 domains. Averages in each domain were compared by gender, age, and hospital identity, attractiveness, and setting. All statistical calculations were performed using SPSS/PC, and means were compared using t-tests. RESULTS: Analysis designed to evaluate outcomes between each of the possible 54 pairs of hospitals comparisons revealed statistically significant differences as often as 44% of the time in some outcomes measures (logistics), but as rarely as 7% of the time in others (billing function). Clinically significant differences (>2 units per scale) were frequently evident, although the ranges differed dramatically depending on the domains surveyed. Although age, gender, and race/ethnicity were generally not predictive of satisfaction, non-urban setting was correlated with greater patient satisfaction. CONCLUSION: By having access to patient satisfaction comparisons among hospitals, patients are empowered to make better choices, employers can identify and adapt to patient preferences, and administrators can improve the services delivered and decrease health care costs by improving efficiency. Although our study was somewhat limited by patient selection biases, the study's results suggest that Internet-based tools of comparison will enable patients to make free and informed decisions about their health care by comparing local hospitals and voting on their impressions of the facilities from which they receive care.

A comparison of consecutive off-pump versus conventional coronary artery bypass.

BACKGROUND: Coronary revascularization on the beating heart is an attractive alternative to conventional coronary artery bypass grafts (CCABG), but remains controversial. Our study compares the outcomes of consecutive patients undergoing off-pump CABG (OPCABG) with a group of similar patients undergoing consecutive CCABG. METHODS: A retrospective analysis of 268 patients who underwent elective CABG between July 1998 and July 1999 at St. Michael's Medical Center yielded 134 consecutive patients who underwent OPCABG and 134 consecutive patients who had CCABG. Patients' medical charts were reviewed for age, preoperative risk factors, operative findings, postoperative complications, and length of stay (LOS). RESULTS: The two cohorts were well matched, with similar ages (66.4 +/- 11.2 for OPCABG vs. 65.8 +/- 10 for CCABG, p = 0.66) and preoperative ejection fractions (EF) (44 +/- 13 vs. 44 +/- 12, p = 0.85). There were no hospital mortalities, and there were five conversions to cardiopulmonary bypass. The OPCABG group had a significantly shorter ICU and postoperative LOS. CONCLUSIONS: Our data suggests that a fair number of patients are potential candidates for OPCABG, the only contraindications being technical limitations or the surgeon's comfort level. Six- to twelve-month follow-up indicates that OPCABG can be performed safely with a decrease in LOS, and should be part of the surgeon's armamentarium.

Comparison of right and left ventricular responses to left ventricular assist device support in patients with severe heart failure: a primary role of mechanical unloading underlying reverse remodeling.

BACKGROUND: Left ventricular assist devices (LVAD) reverse ventricular, myocardial, and systemic abnormalities characteristic of severe heart failure (reverse remodeling). The relative contributions of hemodynamic unloading and normalized biochemical milieu to reverse remodeling are unknown. METHODS AND RESULTS: Structural and functional characteristics were measured from 53 hearts of patients undergoing transplantation without LVAD support (medical support) and 33 hearts from patients receiving a median of 46 days of LVAD support (range, 8 to 360 days). Compared with medical support alone, patients receiving LVAD support for >/=30 days had higher central venous pressures (11+/-6 versus 8+/-5 mm Hg, P=0.04), lower pulmonary artery diastolic pressures (14+/-9 versus 21+/-9 mm Hg, P=0.01), and higher cardiac outputs (5.1+/-1.6 versus 3.7+/-1.0 L/min, P<0.001). In LVAD versus transplantation hearts, V(30) (ex vivo volume yielding ventricular pressure of 30 mm Hg) was decreased in the left ventricle (LV) (179+/-75 versus 261+/-118 mL, P=0.005) but not in the right ventricle (RV) (140+/-59 versus 148+/-52 mL, P=NS). LV myocyte diameter decreased more significantly after LVAD support (17%, P=0.05) than in the RV (11%, P=NS). Compared with transplantation, LVAD support increased normalized SERCA2a content in the LV (0.51+/-0.26 versus 1.04+/-0.34, P<0.001) but not in the RV (0.48+/-34 versus 0.67+/-0.55, P=NS). Finally, LVAD support improved force-frequency relations of isolated superfused LV trabeculae (P=0.01) but not RV trabeculae. CONCLUSIONS: Reduction of hemodynamic load is a primary factor underlying several important features of reverse remodeling. These findings do not preclude a possible primary role of neurohormonal factors underlying other facets of reverse remodeling during LVAD support.

Long-term outcomes after cardiac transplantation: an experience based on different eras of immunosuppressive therapy.

BACKGROUND: Constantly changing practices in heart transplantation have improved posttransplant survival in patients with end-stage heart disease. The objective of this study was to evaluate long-term outcomes in different eras of immunosuppressive therapy after cardiac transplantation at a single center during a two-decade period. METHODS: A retrospective review of 1,086 consecutive cardiac allograft recipients who underwent transplantation between 1977 to 1999 was performed. Patients were divided into four eras based on type of immunosuppressive therapy: era 1 = steroids, azathioprine (n = 26, February 1977 to March 1983), era II = steroids, cyclosporine (n = 43, April 1983 to April 1985), era III = cyclosporine, steroids, azathioprine (n = 752, April 1985 to December 1995), era IV = cyclosporine, steroids, mycophenolate mofetil (n = 315, January 1996 to October 1999). RESULTS: The actuarial survival of the entire cohort of 1,086 patients undergoing cardiac transplantation was 79%, 66%, and 49% at 1, 5, and 10 years, respectively. There were significant trends in recipient age and gender distribution among the four eras with increasing proportion of older age (> 60 years) and female recipients in eras III and IV (p = 0.001 and 0.02). Early mortality and long-term survival improved significantly over all eras (p < 0.001). Rejection as a cause of death decreased over time (era I, 24%; era II, 21%; era III, 15%; era IV, 9%; p = 0.02), whereas the contribution of transplant coronary artery disease as a cause of death remained unchanged. CONCLUSIONS: Cardiac transplantation provides satisfactory long-term survival for patients with end-stage heart failure. The improving outcomes in survival correlate with improved immunosuppressive therapy in each era. Although the reasons for improvement in survival over time are multifactorial, we believe that changes in immunosuppressive therapy have had a major impact on survival as evidenced by the decreasing number of deaths due to rejection.

Pretransplant cachexia and morbid obesity are predictors of increased mortality after heart transplantation.

BACKGROUND: Extremes in body weight are a relative contraindication to cardiac transplantation. METHODS: We retrospectively reviewed 474 consecutive adult patients (377 male, 97 female, mean age 50.3+/-12.2 years), who received 444 primary and 30 heart retransplants between January of 1992 and January of 1999. Of these, 68 cachectic (body mass index [BMI]<20 kg/m2), 113 overweight (BMI=>27-30 kg/m2), and 55 morbidly obese (BMI>30 kg/m2) patients were compared with 238 normal-weight recipients (BMI=20-27 kg/m2). We evaluated the influence of pretransplant BMI on morbidity and mortality after cardiac transplantation. Kaplan-Meier survival distribution and Cox proportional hazards model were used for statistical analyses. RESULTS: Morbidly obese as well as cachectic recipients demonstrated nearly twice the 5-year mortality of normal-weight or overweight recipients (53% vs. 27%, respectively, P=0.001). An increase in mortality was seen at 30 days for morbidly obese and cachectic recipients (12.7% and 17.7%, respectively) versus a 30-day mortality rate of 7.6% in normal-weight recipients. Morbidly obese recipients experienced a shorter time to high-grade acute rejection (P=0.004) as well as an increased annual high-grade rejection frequency when compared with normal-weight recipients (P=0.001). By multivariable analysis, the incidence of transplant-related coronary artery disease (TCAD) was not increased in morbidly obese patients but cachectic patients had a significantly lower incidence of TCAD (P=0.05). Cachectic patients receiving oversized donor hearts had a significantly higher postoperative mortality (P=0.02). CONCLUSIONS: The risks of cardiac transplantation are increased in both morbidly obese and cachectic patients compared with normal-weight recipients. However, the results of cardiac transplantation in overweight patients is comparable to that in normal-weight patients. Recipient size should be kept in mind while selecting patients and the use of oversized donors in cachectic recipients should be avoided.

A regional survey of health insurance coverage for complementary and alternative medicine: current status and future ramifications.

OBJECTIVE: The purpose of this survey is to evaluate the extent of health insurance coverage for complementary and alternative medicine (CAM) within one region in the United States, a study prompted by the increased utilization of CAM. DESIGN: Prospective telephone interview of health insurance representatives. LOCATION: A contiguous three-state area (New York, New Jersey, and Connecticut) in the North-east. RESULTS: Almost all of the insurers surveyed cover chiropractic services. Less than half of the insurers reimburse acupuncture, usually for chronic pain management. Coverage for massage therapy is minimal and usually associated with physical therapy or chiropractic treatment. Other CAM services receive negligible coverage. CONCLUSIONS: Current health insurance coverage of CAM is limited essentially to chiropractic medicine, acupuncture and massage therapy. Coverage of CAM is made confusing by different policies, practitioner requirements, and health plans within each carrier.

Surgical treatment of atrial fibrillation using radiofrequency energy.

BACKGROUND: The Maze III procedure for atrial fibrillation (AF) is effective but has not been used widely due to its complexity, bleeding risk, and added operative time. Surgical radiofrequency ablation may simplify the procedure and make intraoperative correction of AF more accessible and widely performed. METHODS: Endocardial pulmonary venous isolation was performed on 48 patients with AF undergoing concurrent operation using temperature-controlled radiofrequency energy delivered through a hand-held flexible probe. Additional right-sided lesions were made at the surgeon's discretion. RESULTS: Forty-two patients were appropriate for analysis (6 died). These patients had an AF duration of 4.8 +/- 6.4 years. At a mean follow-up of 138 +/- 96 days, 34 patients were in sinus rhythm. We were unable to demonstrate a difference in outcome based on AF duration, left atrial size, or addition of right-sided lesions. CONCLUSIONS: Radiofrequency atrial ablation was effective in 81% of patients with AF at restoring sinus rhythm at an average follow-up of 4 months. This procedure is simple to perform and should broaden the number of patients that receive an AF treatment procedure during concurrent cardiac operation.

Surgical management of valvular disease in patients requiring left ventricular assist device support.

BACKGROUND: Success with long-term implantable left ventricular assist devices (LVAD) has led to increased use in patients previously thought to be unsuitable for mechanical circulatory assistance. Patients with preexisting or newly diagnosed valvular disease have been traditionally excluded from device placement. The purpose of this study was to review our experience with LVAD support in patients with valvular disease and to develop a management algorithm for these difficult patients. METHODS: We reviewed the clinical records of 199 consecutive patients who received the ThermoCardiosystems, Inc, HeartMate Pneumatic or Vented Electric LVAD. There were 18 patients (9%) who required surgical management of native or prosthetic valvular disease during LVAD implantation. RESULTS: Suture or patch closure of the aortic valve was performed in 6 patients, aortic valve plication and repair in 1 patient, mitral valve repair in 4 patients, and tricuspid valve annuloplasty in 5 patients. Two patients with mechanical mitral valve prostheses were treated with postoperative warfarin anticoagulation. Fifteen of the 18 patients with valvular pathology survived the immediate postoperative period (17% mortality). Eleven patients have either undergone transplantation or continue to be supported with an LVAD (61%). Operative mortality in LVAD patients without concomitant valve repair was 18% (n = 33) with a late mortality of 7% (n = 13). Seven of these late deaths occurred in patients who received a device as destination therapy. In the remaining 6 patients, the cause of death was sepsis (n = 2), multisystem organ failure (n = 2), driveline rupture (n = 1), and massive gastrointestinal bleed (n = 1). CONCLUSIONS: Preexisting native or prosthetic valve pathology does not increase the immediate perioperative risk of LVAD insertion; however, these patients continue to pose a challenge for postoperative management while awaiting transplantation.

A new off-pump technique for thoratec right ventricular assist device insertion.

The need for right ventricular support as an adjunct to left ventricular assistance is uncommon. When required, the insertion of a right ventricular assist device may be complicated by preexisting hepatic dysfunction, coagulation abnormalities, and renal failure, all of which are exacerbated by cardiopulmonary bypass. We report a technique for insertion of a right ventricular assist device without the need for cardiopulmonary bypass.