Search PubMed⌕ Search

Biomedical subjects

O H Frazier

Publications and source records attributed to O H Frazier.

At least 19 recordsLinked to original sources

Initial experience with non-thoracic, extraperitoneal, off-pump insertion of the Jarvik 2000 Heart in patients with previous median sternotomy.

BACKGROUND: Successful implantation of left ventricular assist devices (LVADs) in patients with previous median sternotomy remains challenging. METHODS: Seven patients underwent implantation of a Jarvik 2000 Heart by an extrathoracic, extraperitoneal, sub-costal surgical approach, which allows easy exposure of the diaphragmatic surface of the heart and the supraceliac aorta. All patients were at very high risk and were receiving high doses of inotropic agents to maintain their cardiac function. All had undergone prior median sternotomy. We compared data for blood loss and intensive care unit (ICU) stay with those of 15 patients in whom the HeartMate I vented electric LVAD was placed through a re-do sternotomy incision. RESULTS: All 7 patients survived the surgical procedure for implantation of the Jarvik 2000. All 7 patients were rapidly rehabilitated and had a short stay in the ICU (mean 3.3 days, range 1 to 8 days), as compared with the re-do HeartMate patients (mean 10.3 days, range 3 to 33 days) (p = 0.005). The average 12-hour blood loss was 635 ml in the Jarvik patients compared with 2,405 ml in the re-do HeartMate patients (p = 0.028). The cardiac index improved significantly in all Jarvik patients. CONCLUSIONS: The extrathoracic, extraperitoneal, sub-costal surgical approach is less invasive than a median sternotomy and allows the Jarvik 2000 to be implanted quickly and without cardiopulmonary bypass (CPB). By avoiding CPB and an extensive mediastinal dissection, bleeding is decreased in these hypocoagulable patients with compromised end-organ function. The decreased operative morbidity and mortality associated with this technique may allow consideration of the Jarvik 2000 Heart for safe and effective implantation in home-bound New York Heart Association (NYHA) Class III and IV patients.

Blood Loss, Surgical↗

Mechanical reliability of the Jarvik 2000 Heart.

BACKGROUND: Device failure is a limitation of permanent mechanical circulatory support. We studied the mechanical reliability of the Jarvik 2000 Heart, an axial flow pump with ceramic bearings designed to provide more than 10 years' durability. METHODS: The Jarvik 2000 Heart was implanted in 102 patients between April 2000 and December 2004. Eighty-three pumps with an abdominal driveline were implanted as a bridge-to-transplantation, and 19 with postauricular power supply as lifetime therapy. Eighteen pumps were recovered intact after clinical use and run continuously on the bench to further assess durability. RESULTS: No implantable component failure occurred either in patients or during bench testing. The cumulative pump run-time was 110 years: 59 years overall in vivo and 51 years in vitro. The mean support time for bridge-to-transplant recipients was 159 days, and for discharged lifetime-therapy recipients 551 days. Six recipients were supported moer than 2 years, with the longest ongoing approaching 5 years. External cables caused three system failures, with a 95% freedom from system failure at 4 years. Device malfunctions, related to external cables (9) and lack of a backup battery (1), caused no adverse consequences. Before introduction of noncorrosive, gold-plated stainless steel connectors, corrosion was observed on three connectors to the retroauricular power supply. CONCLUSIONS: The Jarvik 2000 Heart has had no implantable component failure. Meaningful durability data and failure mode can only be established by real-time testing in patients. The reliability and dependability of this device, in addition to the exchangeability of external components, give promise for long-term circulatory support in critically ill heart failure patients.

Equipment Failure Analysis↗

Is native aortic valve commissural fusion in patients with long-term left ventricular assist devices associated with clinically important aortic insufficiency?

BACKGROUND: Long-term left ventricular assist device (LVAD) support diminishes flow through the native aortic valve and decreases valve motion. This may cause aortic valve commissural fusion. The clinical importance of such fusion is not well understood. METHODS: Thirty-three consecutive patients receiving long-term LVAD support were followed up until transplantation or death. In each case, the native aortic valve was examined pathologically for commissural fusion. Pathology findings were correlated with hemodynamic performance as assessed by both LVAD pump flow and echocardiography. RESULTS: Seventeen of the 33 patients had some degree of native aortic valve commissural fusion. Four patients had fusion at 2 commissures; of these, 2 had clinically significant native valve aortic insufficiency (2+ or greater), and 1 exhibited trace insufficiency of the native aortic valve. Thirteen patients had fusion at only 1 aortic commissure; of these, 2 had clinically significant aortic insufficiency (2+ or greater), and 3 had trace or mild (1+) insufficiency of native aortic valve. Two of the 4 patients with fusion at 2 commissures required increased LVAD support of >3 liters/min/cm2. No patient with fusion of only 1 commissure required increased LVAD support. Three patients with no commissural fusion of the aortic valve required increased LVAD support secondary to sepsis. CONCLUSIONS: Commissural fusion of the native aortic valve occurs in a significant number of patients receiving long-term LVAD support and can necessitate increased levels of LVAD support. Recognition of this phenomenon may allow development of strategies to minimize commissural fusion and extend LVAD pump life.

Adult↗

Hemodynamics and patient safety during pump-off studies of an axial-flow left ventricular assist device.

BACKGROUND: Axial-flow left ventricular assist devices (LVADs), when inactivated, may result in regurgitant blood flow. We assessed the effects of regurgitant pump flow with the intraventricular Jarvik 2000 Heart LVAD (Jarvik Heart, Inc., New York, NY) on hemodynamics and patient safety under pump-off conditions. METHODS: Thirty patients being supported by a Jarvik 2000 as a bridge to heart transplantation underwent pump-off studies. Hemodynamics, vital signs and cognitive function were monitored; Doppler echocardiographic studies were done with the pump turned off for 5 minutes if tolerated. Regurgitant flow was assessed in terms of the difference between left ventricular and right ventricular outflow tract cardiac output (LVOT CO - RVOT CO). RESULTS: During pump-off periods, the mean regurgitant flow was 0.42 +/- 0.41 liter/min, and the mean arterial blood pressure was 63.1 +/- 11.6 mm Hg. There was no regurgitant flow when the pump was on. Three patients did not tolerate the pump being off for periods of 5 minutes; in these tests, the mean regurgitant flow rate was 0.54 +/- 0.50 liter/min, the mean arterial blood pressure was 52.8 +/- 9.8 mm Hg, and the mean pump-off time was 3.1 +/- 1.1 minutes. All patients remained conscious during the pump-off period, and none showed lasting adverse effects. CONCLUSIONS: Our findings suggest that patients being supported with the axial-flow Jarvik 2000 Heart LVAD can generally tolerate pump-off times of 5 minutes.

Adult↗

Fatal pulmonary microthrombi during surgical therapy for end-stage heart failure: possible association with antifibrinolytic therapy.

BACKGROUND: Maintaining hemostasis in patients with end-stage heart failure undergoing cardiac surgery is always challenging. These patients have chronic hepatic insufficiency, resulting in derangement of coagulation. In addition, they are commonly receiving both systemic anticoagulation (warfarin or heparin) and antiplatelet therapy. The introduction of antifibrinolytics has had a significant effect on postoperative coagulopathy. We report fatal pulmonary microthrombi in patients receiving antifibrinolytics who developed suprasystemic pulmonary artery pressures and right heart failure that was impossible to overcome despite insertion of a right ventricular assist device. METHODS: We reviewed the surgical procedure and autopsy reports to identify patients with high pulmonary artery pressures caused by pulmonary microthrombi after a cardiac surgical procedure for end-stage heart failure. Patient demographics and preoperative, intraoperative, and postoperative variables were collected from a retrospective review of the patients' medical records. RESULTS: We identified 9 patients (7 men and 2 women; mean age, 45 +/- 16 years) who died of pulmonary microthrombi after cardiac surgery between January 1997 and January 2004. Surgical procedures included 5 left ventricular assist device implantations, 2 heart transplantations, and 2 left ventricular reconstructions with mitral valve repair or replacement. Eight patients received aprotinin, and 1 patient received epsilon-aminocaproic acid immediately before and during cardiopulmonary bypass. All patients had severe suprasystemic pulmonary artery pressures after protamine administration for heparin reversal, a complication that proved fatal in all cases. Intraoperative wedge biopsy of the lungs revealed multiple microthrombi within capillaries and in the small- and medium-sized pulmonary arterioles. CONCLUSION: We report 9 cases for which fatal pulmonary microthrombi might be associated with the use of prophylactic antifibrinolytic therapy. Mortally ill patients with multiorgan failure who are receiving systemic anticoagulation and undergoing surgical procedures require careful perioperative monitoring to identify potential hazards. Anticoagulation and antifibrinolytic therapy protocols may require adjustment in such patients.

Adult↗

Off-pump insertion of an extracorporeal LVAD through a left upper-quadrant incision.

Insertion of an extracorporeal left ventricular assist device for temporary ventricular support via median sternotomy can be challenging in patients with a history of cardiac surgery, because these patients often poorly tolerate the lengthy dissection and cardiac manipulation necessary for exposure of the left ventricular apex and ascending aorta. Our approach, transdiaphragmatic left ventricular inflow cannulation with return through a graft sewn to the supraceliac aorta, can be accomplished through a left upper-quadrant abdominal incision without entering the peritoneal cavity, mediastinum, or left hemithorax. Repeated sternotomy and mediastinal dissection are thus avoided. To our knowledge, this report documents the 1st use of this technique for insertion of an extracorporeal pulsatile ventricular assist device for temporary ventricular support.

Aged↗

Saphenous vein graft flow during left ventricular assistance with an axial-flow pump.

The effects of continuous-flow support on bypass graft flow have not been quantified clinically. Continuous-flow left ventricular assist devices unload the left ventricle throughout the cardiac cycle, which narrows pulse pressure and converts passive left ventricular filling during diastole to active flow throughout the cardiac cycle. We report the case of a 63-year-old man with severe congestive heart failure who underwent coronary artery bypass grafting and was supported with an axial-flow pump. In this patient, saphenous vein graft flow during left ventricular assistance provided adequate coronary perfusion.

Coronary Artery Bypass↗

Successful ventricular remodeling with coronary artery bypass grafting and mitral valve repair in a patient with severe heart failure.

Left ventricular remodeling is becoming a frequent treatment for severe heart failure, but its use in combination with other surgical techniques is controversial. We report a case in which left ventricular remodeling was combined with coronary artery bypass grafting and mitral valve repair to treat a patient with severely depressed ejection fraction, mitral insufficiency, coronary artery disease, and a recent history of myocardial infarction. Cardiac function improved after the combined treatment. This case suggests that left ventricular remodeling can be used safely and effectively in conjunction with other surgical techniques.

Cardiac Surgical Procedures↗

Orthotopic retransplantation in heterotopic transplant recipients: 3 case reports.

We report 3 patients who initially underwent heterotopic transplantation due to a size mismatch but then later underwent orthotopic retransplantation because of heart failure. In each case, the heterotopic graft was left in place, the native heart was removed, and the new allograft was placed orthotopically. This technique resulted in reduced postoperative morbidity and excellent long-term outcomes.

Adult↗

Aorta-to-left-atrial shunting through a previously performed heterotopic heart transplant: an unusual complication of orthotopic re-transplantation.

Heterotopic heart transplantation is rarely performed today, except in cases of recipient-donor size mismatch and when addressing complications associated with recipient pulmonary artery hypertension. As in orthotopic cardiac transplantation, occurrence of allograft vasculopathy occasionally calls for re-transplantation. Although orthotopic re-transplantation without removal of the heterotopic allograft has been described previously, we report the case of a patient who presented with an unusual complication.

Aged↗

Advanced heart failure: feasibility study of long-term continuous axial flow pump support.

AIMS: A lack of donor hearts has stimulated interest in using blood pumps to treat severe heart failure. We tested the hypothesis that a new continuous flow circulatory assist device could be employed safely to relieve symptoms of heart failure and evaluated the potential to prolong life. METHODS AND RESULTS: An intracardiac axial flow pump was implanted in 17 heart failure patients [idiopathic dilated (12), ischaemic (4), or amyloid cardiomyopathy (1)]. All were deemed ineligible for transplantation. Implantation of the device was by left thoracotomy (15) or median sternotomy (2). Power delivery was by a skull-mounted titanium pedestal. All patients survived surgery. None needed right ventricular support. There were three hospital deaths, two early from subdural haematoma and aortic thrombosis, one late after switching to transplantation. A total of 14 patients left hospital with a cumulative support-time of 15.9 years (median: 293 days, interquartile range: 286 days, 1-44 months). Actuarial 1-, 2-, and 3-year survivals were 56, 47, and 24%, respectively. There was no pump failure. Quality of life scores improved. Two superficial pedestal infections were successfully treated. Four patients had cerebral thrombo-embolism: two early events attributed to inadequate anticoagulation and two late with near-complete resolution. An improved anticoagulant regime addressed this problem. Late death occurred in five patients from battery disconnection, subdural haematoma, bowel ischaemia, respiratory failure, and after cardiac transplantation. CONCLUSION: Continuous flow blood pumps provided symptomatic relief of severe heart failure with high quality of life. Event-free survival reached 4 years. Analysis of adverse events led to improved management strategies. There is potential for widespread use of blood pumps in the community. A controlled trial is required.

Aged↗

Lung cancer after heart transplantation: a 17-year experience.

BACKGROUND: The effects of heart transplantation on lung cancer incidence in heart transplant recipients are unclear. METHODS: In an observational study, we retrospectively reviewed the charts of all patients undergoing heart transplantation at our institution from July 1982 to July 1999. Data on lung cancer incidence, risk factors, treatment, and outcome were collected. RESULTS: Five hundred seventy-two patients (mean age, 50 +/- 11 years; range, 18 to 73) were considered at risk for lung cancer. Of these, 324 (57%) had a more than 20 pack-year history of smoking before transplantation. Lung cancer developed in 2 patients 1 year or less after transplantation and in 8 patients more than 1 year after transplantation (incidence, 2.2 per 1,000 patients per year of follow-up). Non-small cell lung cancer was diagnosed in all cases. Median survival was 10.8 months (range, 2 to 37.5). Routine annual chest radiographs after transplantation enabled early diagnosis in 5 cases (stages Ia and IIa), which correlated with better mean survival (28.1 months [range, 19 to 37.5] versus 5.1 months [range, 2 to 10.8]; p = 0.0002). CONCLUSIONS: The incidence of lung cancer in our population of heart transplant recipients appears to be no higher than in nontransplant populations with similar risk factors (ie, smoking and age). Routine radiographic imaging of transplant recipients may allow earlier detection of lung cancer and thus offer a survival benefit.

Adolescent↗

Evaluation of myocardial function in patients with end-stage heart failure during support with the Jarvik 2000 left ventricular assist device.

In 2 patients with the Jarvik 2000 left ventricular assist device (LVAD), we assessed left ventricular systolic function through pressure-volume loops and E(max) at the beginning and end of the support period to potentially predict the possibility of pump removal without transplantation. Immediately before LVAD implantation and explantation, pressure and volume measurements were made with catheters and echocardiography, respectively, the E(max) being calculated from the slope of the pressure-volume loops, and the left ventricular ejection fraction (LVEF) being estimated by echocardiography. Transplantation was performed after 14 and 62 days, respectively, during which the LVEF increased by 75% (from 12% to 21%) in Patient 1 and remained unchanged (from 16% to 18%) in Patient 2, whereas the E(max) increased from 0.63 and 0.42 mm Hg/ml, respectively, to 1.31 and 1.07 mm Hg/ml, reflecting a 107% and 155% improvement. In these 2 cases, the E(max) was a more reliable indicator of intrinsic myocardial contractility than was the LVEF.

Cardiac Catheterization↗

Gastrointestinal bleeding from arteriovenous malformations in patients supported by the Jarvik 2000 axial-flow left ventricular assist device.

The long-term effects of axial-flow mechanical circulatory support in humans are unclear. We report 3 cases of chronic gastrointestinal bleeding after implantation of a Jarvik 2000 axial-flow left ventricular assist device. The bleeding was refractory to aggressive management and in 2 cases resolved only after orthotopic cardiac transplantation.

Aged↗