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M Loebe

Publications and source records attributed to M Loebe.

At least 55 records · Page 3Linked to original sources
PubMed1999

Medium-term results of heart transplantation using donors over 63 years of age.

BACKGROUND: The continual shortage of hearts for transplantation (HTx) led to the expansion of the donor pool by accepting older donors. We compared the medium-term follow-up of patients after HTx with older hearts (over the age of 63 years) with those of patients after HTx with younger hearts. PATIENTS AND METHODS: Since April 1994 we have used hearts for HTx from donors older than the age of 63 years. Until November 1998, 309 HTx and 9 re-HTx were performed in 309 adults with a mean age of 50.7+/-10.9 years (range 17-68 years). There were 252 men and 57 women. The patients were divided into two groups: group I--donor age under 63 years (296 patients, mean age 50.4+/-11 years; mean donor age 38.1+/-13 years; mean follow-up 1.7+/-1.6 years); group II-donor age of more than 63 years (13 patients, mean age 57.4+/-5.6 years; mean donor age 65.1+/-2.1; mean follow-up 2.2+/-1.6 years). There were no differences in the etiology of heart failure, gender, or ischemia time between the groups. The patients in group II were significantly older (P = 0.008). Multiple factors were analyzed in the groups, which included changes in the left/right ventricle ejection fraction, early postoperative mortality (up to 30 days), cumulative survival rates and cardiac-dependent morbidity [myocardial infarction, malignant arrhythmias, coronary stenosis (>50% in one of the main coronary arteries) and transplant vasculopathy]. Additionally, freedom from cytomegalovirus infection (rise of titer or seroconversion) and freedom of acute rejection episodes grade > or =2 (International Society of Heart & Lung Transplantation [ISHLT]) were analyzed. RESULTS: After 1 year mean left and right ventricle ejection fraction were good in both groups and did not significantly change for up to 2 years. No Re-HTx was performed in group II. The early postoperative mortality was similar in both groups (P = 0.8). Also, the cumulative survival rates were similar in both groups (P = 0.87). Long-term cardiac morbidity was lower in group I (P = 0.03). The long-term freedom from cytomegalovirus infection in group I was significantly higher when compared with group II (P = 0.0002). The long-term freedom from severe rejection episodes was similar in both groups (P = 0.3) CONCLUSION: The study found a significant increase in long-term cardiac morbidity due to more focal coronary stenosis in group II, and freedom from cytomegalovirus infection, but did not find significant differences in the long-term survival between patients who received hearts from donors of up to 63 years of age and from those more than 63 years. The acceptance of donors older than 63 years old for HTx does not worsen the outcome of the recipients. The careful selection of older donors, with close monitoring of the coronary situation after HTx and expanded indications for revascularization of older hearts, could make HTx with older hearts, even in older recipients, a safe option.

Adolescent↗
PubMed1999

Effects of HMG-CoA reductase inhibition on PDGF- and angiotensin II- mediated signal transduction: suppression of c-Jun and c-Fos in human smooth muscle cells in vitro.

Hydroxymethylglutaryl-Coenzyme A (HMG-CoA) reductase inhibitors were shown to be effective in primary and secondary prevention of coronary heart disease. The beneficial effect of statins is generally attributed to their cholesterol lowering activity. However recent work points to additional cholesterol independent effects of these drugs on cellular signal transduction. In this study it was investigated whether HMG-CoA reductase inhibition could affect induction of the transcription factors c-Jun and c-Fos in smooth muscle cells, which play an important role in atherogenesis. SMC were preincubated for 12 h with or without lovastatin (5 microM) and subsequently stimulated with platelet derived growth factor (PDGF, 10 ng/ml) or angiotensin II (0.1 microM) for 1, 2, 4 and 12 h or with phorbol myristate acetate (100 pM) for 2 h. Stimulation in the absence of the HMG-CoA reductase inhibitor led to a significant induction of c-Jun and c-Fos. Lovastatin inhibited, PDGF-, angiotensin II- and PMA-mediated induction. Concomitant addition of mevalonate, farnesylpyrophosphate and geranylgeranylpyrophosphate prevented the effects of HMG-CoA reductase inhibition resulting in rescued expression of c-Jun and c-Fos. The suppression of these transcription factors was associated with a complete growth arrest. Viability was not affected by pretreatment with the HMG-CoA reductase inhibitor. The data demonstrate that lovastatin can suppress PDGF- and angiotensin II-mediated induction of c-Jun and c-Fos protein in human SMC. This inhibitory effect may prevent activation of numerous growth factor- and cell cycle- genes. Whether these findings contribute to the effects of statins in atherosclerosis remains to be further investigated.

Angiotensin II↗
PubMed1999

Cardiac recovery in dilated cardiomyopathy by unloading with a left ventricular assist device.

BACKGROUND: Lasting recovery from intractable end-stage dilated cardiomyopathy, which occurs with ventricular unloading, has recently been demonstrated in 5 patients. Here our extended clinical experience with the "weaning" concept is presented. METHODS: In 19 patients (23 to 65 years) with intractable end-stage dilated cardiomyopathy, ventricular assist devices were explanted after support periods of up to 26 months, when repeat off-pump studies had shown either restoration of cardiac function (left ventricular ejection fraction, > 45%) and dimensions (left ventricular internal diameter in diastole, < 55 mm) or partial recovery (left ventricular ejection fraction between 35% and 40%) with serious complications on the device. At the time of device placement left ventricular ejection fraction was below 20% and left ventricular internal diameter in diastole more than 64 mm and bridge-to-transplantation had been planned. RESULTS: Seven patients with persistently restored cardiac function for more than 8 months and 5 patients for less than 5 months after weaning were studied. Five patients with recurrent heart failure died within 4 to 8 months after explantation. Four patients had to be transplanted and 2 died for reasons unrelated to cardiac function. An individual optimal left ventricular ejection fraction and left ventricular internal diameter in diastole was reached before pump removal was actually conducted in all patients. These parameters gradually deteriorated until pump removal. CONCLUSIONS: Lasting recovery can be reached by ventricular unloading in a subset of patients with intractable end-stage dilated cardiomyopathy. Obviously, there is an individual optimum of recovery that cannot be further improved by prolonged unloading.

Adult↗
PubMed1999

The European experience of Novacor left ventricular assist (LVAS) therapy as a bridge to transplant: a retrospective multi-centre study.

OBJECTIVE: Artificial heart devices have suffered from a negative press based on the early Jarvik experience of the 1980s. This is in stark contrast to realities of current left ventricular assist (LVAS) therapy. The Novacor N100 PC wearable left ventricular assist system (LVAS) was introduced in Europe in late 1993. This system allows implanted recipients to be completely autonomous with the system controlled by a small computer and powered by rechargeable batteries. This report represents the initial European experience with the Novacor LVAS. METHODS: Since the system was introduced with regulatory approval as a commercial product, clinicians were not bound by the constraints of a study protocol and only minimal data were collected. This report presents the results of a retrospective study of 118 consecutive patients who had the LVAS implanted as a bridge to transplant, in 19 centres over the three year period ending in November 1996. RESULTS: Mortality and morbidity varied widely between centres. The median implant time was 115 days (0-585 days) and 33% of patients returned home, supported by the LVAS. The overall survival on LVAS was 64%. The major causes of death were infection (14%) and MOF (6%). There were no significant device or system failures despite a cumulative patient experience of 24.8 years outside of a hospital environment. Patient selection and management varied greatly between centres and this was reflected in disparate outcomes. CONCLUSIONS: Optimal selection and management of LVAS patients has still to be established. While the data available for this report lacked the detail necessary to demonstrate direct causal relationships between selection and management, it was clear from the inter-centre differences that these two factors have a major impact on outcomes. This early experience has directed attention towards improved management regimes. Given the results obtained from the best centres and the ability to discharge patients to lead near-normal lives in the community, the authors believe that the Novacor LVAS now offers a real therapeutic alternative for selected end-stage heart failure patients for whom a donor heart is unavailable or who are unsuitable for transplantation.

Adolescent↗
PubMed1999

Coronary artery bypass grafting after orthotopic heart transplantation.

OBJECTIVE: Graft coronary disease (GCD) remains the major determinant of long-term survival after heart transplantation. Therapeutic strategies for the prevention or retardation of GCD in the cardiac allograft are limited, and palliative surgical coronary revascularization has been attempted. The aim of this report was to retrospectively analyze our results of coronary artery bypass grafting after cardiac transplantation. This paper correlates the outcome of patients with the pathohistological and angiographic type of lesion in order to identify transplant recipients who may profit from surgical myocardial revascularization. METHODS: Seven patients with a mean age of 55 years (range 45-61 years) underwent coronary artery bypass grafting as a result of GCD at a mean of 67 months (range 6-128 months) after cardiac transplantation. By the inclusion of the clinical history and the angiographic pattern of GCD lesions, the primary indications for surgical revascularization, operative results, pathohistological studies and follow-ups were examined. RESULTS: Elective surgery was performed in two patients with proximal, severe triple vessel disease (Type A lesion) and in one patient in whom the primary reason for cardiac surgery was severe tricuspid regurgitation. This patient electively received a tricuspid valve replacement and concomitant single vessel bypass surgery for proximal GCD (Type A lesion). Emergency surgery was performed in four patients: preoperatively three patients post-infarction developed worsening congestive heart failure, which resulted in low cardiac output syndrome. One patient with combined Types A and B/C lesions required emergency surgery for dissection of the right coronary artery (RCA) after an angioplasty procedure. Angiographically all these patients showed diffuse, distal arteriopathy (combined Type B/C lesions). The electively operated patients (n = 3) and the patient with dissection of the RCA (n = 1) had successful operations and survived beyond hospital discharge (overall survival for coronary artery bypass graft (CABG) in GCD patients 4 out of 7; 57%). All three patients with distal arteriopathy, who underwent emergency surgery, died in hospital from left ventricular failure (43%). The four patients discharged from hospital with a mean follow-up of 10 months (range 2-32 months) are all in good clinical condition. CONCLUSIONS: Coronary artery bypass grafting can be successfully performed in a subgroup of cardiac transplant patients with Type A lesions. However, the state of diffusely diseased distal arteries (Type B/C lesions), which is prevalent in this group of patients, limits the use of bypass surgery.

Biopsy↗
PubMed1999

Ventricular assistance for recovery of cardiac failure.

Mechanical assist devices have been used increasingly to support patients who await heart transplantation. The initial goal was to provide sufficient circulatory function to keep these patients alive and to allow them to recover from secondary organ dysfunction. A recent observation showed an improvement in native heart performance in some transplant candidates who receive support with mechanical assist devices. Under these conditions, myocardial recovery has been mostly restricted to patients with primary dilated cardiomyopathy and with extended periods of ventricular support. Also, the exact mechanisms that lead to substantial myocardial recovery remain unknown. Several investigations have demonstrated improved myocyte performance, reduced fibrosis, reduced cytokine levels, and reduced autoantibodies during long-term mechanical support; therefore, the observation of cardiac recovery during mechanical support is in accordance with currently discussed models of end-stage heart failure.

Heart Diseases↗
PubMed1999

Radiologic anatomy of ventricular assist devices.

Ventricular assist devices (VAD) allow for long-term circulatory support of patients with end-stage heart failure. With the increasing duration of circulatory support, diagnostic imaging plays an important role in the management of patients on a VAD. The aim of our review was to analyze the radiologic features of different VADs. From 1987 to 1996, 319 patients (mean age 42 years, range 3 to 74 years) were treated with a VAD. A Berlin Heart VAD was implanted in 263 of the patients, the univentricular Baxtor Novacor was implanted in three patients, and the univentricular CI Heartmate was implanted in 19 patients. All patients were studied by serial chest radiographs. In addition, 70 patients underwent computed tomography (CT), and five patients underwent electron beam CT. The Berlin Heart VAD was used as a biventricular support system in 218 patients. In all cases, the position of the wire-directed cannulae was identified on the chest radiographs, while the exact position of the cannula tip could be visualized by CT only. The plastic cannulae of both the Novacor and the Heartmate were not discernible on radiographs, but required CT for evaluation. Computed tomography also resolved the metal components of the pumps. The titanium-made pump housing of the Heartmate caused beam-hardening artefacts that might conceal fluid accumulations in the pump pocket. Computed tomography is the standard of reference for examinations of cannula position, pump position, and pump components of ventricular assist devices.

Adolescent↗
PubMed1999

Motion artifacts in cardiac CT. The Novacor left ventricular assist device and its implications for clinical imaging.

PURPOSE: Cardiovascular applications of CT are primarily limited by temporal resolution of the scanner. Recent development in scanner technology has greatly increased temporal resolution. We here describe a standardized method of assessing temporal properties of various CT techniques. MATERIAL AND METHODS: The Novacor left ventricular assist device was mounted in a water-filled circulation phantom and scanned at different pump rates with a spiral CT unit and an electron beam unit. We also evaluated the use of ECG-triggered subsecond scanning on a spiral CT unit. RESULTS: Using the fastest conventional scanning protocol, severe motion artifacts occurred. These artifacts could not be reproduced from image to image, even if the pump rate was adjusted to scan rate (l/s). Electron beam tomography (EBT) reproducibly yielded few artifacts at 100 ms and practically no artifacts at 50 ms scanning time. Even without ECG-triggering, pump motion could be reproduced as a cine-cycle. With the ECG-triggered partial scanning CT technique, limited motion artifacts could be reproduced during diastole at a heart rate of 70-80 beats/min. CONCLUSION: The Novacor ventricular assist device may serve as a benchmark test in the evaluation of new scanning techniques for cardiovascular CT. While EBT presently remains the only CT technique to freeze cardiac motion throughout its cycle, ECG-triggered subsecond scans may, under certain conditions, capture cardiac anatomy in diastole.

Artifacts↗
PubMed1998

[Electron-beam computed tomography in heart surgery].

PURPOSE: Electron beam CT (EBCT) has been devised to improve the imaging of the heart and the great vessels. Therefore, this method is expected to facilitate the imaging workup of patients referred for cardiothoracic surgery. We set out to review the most important surgical issues that can be addressed with this method. METHODS: From June, 1997 until July, 1998, more than 300 patients were referred from cardiothoracic surgery. In a retrospective analysis, diagnostic results were reviewed and compared with surgical findings and the clinical course. RESULTS: Aortocoronary bypass graft occlusions were detected with a sensitivity of 100% and a specificity of 95%. Calcifications of the aorta, pericardium and intracardiac tumors were surgically confirmed in all instances. There was a significant association of the degree of coronary artery calcification and the progression of cardiac allograft vasculopathy in 50 heart transplant recipients. In EBCT of the aorta, a high degree of diagnostic confidence was found for aortic dissection, aortic wall hematoma or aortic perforation. CONCLUSIONS: We conclude that EBCT represents an important diagnostic tool both for surgical planning and postoperative surveillance in cardiothoracic surgery.

Adult↗
PubMed1998

Daily noninvasive rejection monitoring improves long-term survival in pediatric heart transplantation.

BACKGROUND: Acute rejection episodes and transplant vasculopathy (TVP) account for most of the late deaths after heart transplantation in both adults and children. Accumulating evidence indicates that fatal acute rejection and TVP are related to unrecognized and untreated early and ongoing acute rejection. Day-by-day surveillance of the heart and prompt treatment of any rejection may yield improved long-term survival. METHODS: In almost all patients having transplantation at our institution (978 patients since 1986), the intramyocardial electrogram (IMEG) was recorded routinely every day through a telemetry pacemaker and transmitted to our center by telephone modem. Earlier studies showed a substantial voltage drop in the IMEG QRS complex is highly indicative of acute rejection, including humoral rejection. In this study, we reviewed the data from 69 pediatric patients up to 16 years old for the incidence of acute rejection, TVP, and long-term outcome. Diagnostic endomyocardial biopsies were performed in only 10 patients, and recent coronary angiograms from 29 children were reviewed. RESULTS: In 50 children discharged after heart transplantation, IMEG surveillance data for a mean of 2.9 years indicated 72 acute rejection episodes. During follow-up of 1 month to 10.5 years (mean follow-up, 4.4 years), 2 patients died late of causes unrelated to either rejection or TVP. Another patient died of rejection during unrecognized underimmunosuppression nearly 8 years after transplantation and nearly 31/2 years after discontinuing IMEG recordings. Two patients without IMEG recording died of acute rejection or late TVP. In 1 patient, moderate TVP was seen on an angiogram after 41/2 years (incidence, 2.0%; 5-year incidence, 5.6%). CONCLUSIONS: Daily recording of the IMEG can reliably detect early stages of acute rejection episodes, and immediate rejection treatment seems to keep the incidence of TVP low. The IMEG appears better than all the other rejection monitoring protocols currently in use.

Acute Disease↗
PubMed1998

Circulatory support with pneumatic paracorporeal ventricular assist device in infants and children.

BACKGROUND: Mechanical circulatory support in intractable heart failure in children has been limited to centrifugal pumps and extracorporeal membrane oxygenation: Since 1990 small adult-size pulsatile air-driven ventricular assist devices "Berlin Heart" (VAD) and, since 1992 miniaturized pediatric VAD (12, 15, 25, 30 mL pumps), have been used in our institution. Since 1994 the blood-contacting surfaces of the device system have been heparin-coated. In this report the experiences with VAD support in 28 children are presented. METHODS: In 28 children-ages between 6 days and 16 years-the Berlin Heart VAD has been applied for periods of between 12 hours and 98 days (mean, 16.9 days) aiming at keeping the patient alive and allowing for recovery from shock sequelae until later transplantation or myocardial recovery. There were three groups. Group I: with primary intention of "bridge-to-transplantation" in various forms of cardiomyopathy (n = 13) or chronic stages of congenital heart disease (n = 5). Group II: "Rescue" in intractable heart failure early after corrective surgery for congenital heart disease (n = 4) or in early graft failure after a heart transplantation (n = 1). Group III: "Acute myocarditis" (n = 5) aiming at either myocardial recovery or transplantation. Twelve were brought to the operating room under cardiac massage and 25 had been on the respirator for more than 24 hours. RESULTS: Twelve patients died on the system from sequelae of profound shock-multiorgan failure, sepsis, loss of peripheral circulatory resistance-or from hemorrhagic complications (n = 4) or brain death (n = 1). Thirteen patients (groups I and III) were transplanted after support periods of between 3 and 98 days with 7 long-term survivors living now up to 7.5 years (mean, 4.4 years). Three patients (groups II and III) were weaned from the system with two long-term survivors (both in group III). There were no patients in group II who survived and the "rescue" indication has been discarded for VAD since 1992. Such patients are since treated by extracorporeal membrane oxygenation (ECMO) in our institution. Out of the 8 patients placed on VAD during 1996 and 1997, 7 were successfully supported until transplantation or weaning. Thirteen patients were extubated and mobilized on the system. Whereas with the earlier systems thrombi in the blood pumps were seen in 15 instances and 2 patients suffered from thromboembolic complications, no thrombotic events occurred with the heparin-coated systems. CONCLUSIONS: After accumulating clinical experience and several technical improvements since 1990 the use of the pediatric Berlin Heart VAD has matured into a reliable and safe system to keep patients with otherwise intractable heart failure alive until complete myocardial recovery is reached or transplantation becomes feasible. Whereas heart failure early after cardiac operation is now primarily treated by ECMO, acute myocarditis appears to be a promising precondition for complete cardiac recovery during VAD support.

Adolescent↗
PubMed1998

Human cardiac microvascular and macrovascular endothelial cells respond differently to oxidatively modified LDL.

Oxidation of low density lipoproteins (LDL) is considered a key event in the pathogenesis of atherosclerotic lesions. Disturbed generation of coagulatory and anticoagulatory factors by endothelial cells contributes to thrombosis and the progression of atherosclerosis in coronary arteries. In this study, the effects of native LDL (n-LDL) and oxidized LDL (ox-LDL) on human coronary endothelial cells were measured. The reaction of coronary endothelial cells to LDL were compared with those of cardiac microvascular endothelial cells grown under comparable conditions. LDL was isolated by ultracentrifugation and copper oxidized. The degree of oxidation was expressed as malondialdehyd (MDA) equivalents and was 0.78+/-0.14 nM MDA/mg LDL for native LDL and 13.63+/-1.18 nmol MDA/mg LDL for ox-LDL. Basal secretion of t-PA and PAI-1 activity were higher in macrovascular endothelial cells. Incubation of n-LDL in concentrations ranging from 3 to 100 microM/ml LDL-protein did not change t-PA-secretion, PAI-1 activity or procoagulant activity in both cell types. Ox-LDL (3 to 100 microM/ml LDL protein) decreased t-PA secretion in a concentration dependent manner from 30.9+/-1.7 to 13.7+/-30 ng/ml per 24 h per 10(6) cells (P < 0.01), increased PAI-1 antigen from 2772+/-587 to 4441+/-766 ng/ml per 24 h per 10(6) cells (P < 0.05) as well as PAI-1 activity from 34+/-6 to 55+/-9 AU/ml per 24 h per 10(6) cells (P < 0.05) in macrovascular endothelial cells but had only minor effects on microvascular endothelial cells. Procoagulant activity measured as coagulation time, similarly increased only in macrovascular endothelial cells from 197+/-6 to 76+/-6 s/24 h per 10(6) cells (P < 0.05). The effect on PAI-1 secretion showed a dependency to the degree of oxidation and could be completely blocked by the antioxidant probucol. The angiotensin converting enzyme (ACE), which represents an endothelial enzyme not related to coagulation, remained unchanged during incubation with ox-LDL. Basal ACE activity was higher in microvascular endothelial cells. The higher susceptibility of macrovascular endothelial cells to ox-LDL may partially determine the localization of thrombus formation and the development of atherosclerotic plaques in hyperlipidemic patients.

Antioxidants↗
PubMed1998

Coronary angioplasty, bypass surgery, and retransplantation in cardiac transplant patients with graft coronary disease.

BACKGROUND: Graft coronary disease (GCD) remains the single greatest limitation to long-term survival of heart transplant recipients. Therapeutic strategies for the prevention or retardation of GCD in the cardiac allograft are limited; palliative coronary revascularization has been attempted. Because of the high mortality rate associated with advanced forms of GCD our institution offers the option of retransplantation in selected cases. The aim of this study was by analyzing retrospectively the outcomes of angioplasty, coronary bypass grafting, and retransplantation in cardiac transplant patients to attempt to identify subgroups of transplant recipients with graft coronary disease who may profit from myocardial revascularization. METHODS: Of the 989 patients undergoing 1016 heart transplantations (HTx) at our institution between 10/86 and 12/97, all were screened for the development of GCD. Analyzing routinely annual angiography, intracoronary ultrasound in defined study patients, and autopsy findings, GCD was diagnosed in 124 patients (110 male, 14 female) 2 to 107 months after HTx (mean 30 months). RESULTS: PTCA: Fourty-six out of 124 patients underwent 76 angioplasties at a mean of 50 +/- 30 months (range 4-91 mo) following cardiac transplantation. The primary success rate was 96% (73/76). The reason for the unsuccessful angioplasty attempts (n = 3) was failure to completely penetrate a stenosis of LAD in 2 patients and severe dissection of RCA, which required emergency surgery, in one. Angiographic restenosis occurred in 42% (31 of 76 lesions) and was diagnosed 11 +/- 11 months after the first angioplasty. There was no procedure-related death. CABG: Seven patients underwent bypass surgery at a mean of 67 months (range 6-128 months) after HTx. Elective surgery was performed in 2 patients with proximal severe triple-vessel disease (Type A lesion) and in 1 patient with severe tricuspid regurgitation who received a tricuspid valve replacement and concomitant single-vessel bypass surgery for proximal GCD (Type A lesion). One patient with combined Type A and B/C lesions required emergency surgery for dissection of RCA after an angioplasty procedure. Three patients with post-infarction unstable angina developed worsening congestive heart failure which required emergency surgery. Angiographically all these patients showed diffuse, distal arteriopathy (combined Type B/C lesions). The electively operated patients and the patient with dissection of RCA were successfully treated and survived beyond hospital discharge (overall survival for CABG in GCD patients 4/7 = 57%). After a mean follow-up of 10 months (range 2-32 months) all are in good clinical condition. All 3 patients with distal arteriopathy and emergency surgery died in hospital of left-ventricular failure (43%). Retransplantation: Eight patients underwent retransplantation at a mean of 54 months (range 6-96 months) after HTx. Six of 8 patients had successful operations and survived beyond hospital discharge with a one-year-survival rate of 75%. In a mean follow-up of 31 months (5-68 months) 3 of 6 retransplant recipients developed a recurrence of GCD. CONCLUSION: The presence of angiographic distal arteriopathy should be considered a significant factor in patient selection for coronary revascularization procedure. Coronary angioplasty is to be considered as a method of treatment for severe, local stenoses (Type A lesion). PTCA may be applied in these selected cardiac transplant recipients with primary success and complication rates comparable to routine angioplasty but with an increased rate of restenosis especially in small vessels (diameter < 2.5 mm). The distinction between Type A lesions in large (diameter > or = 2.5 mm) and small vessels may be important not only with respect to restenosis but also with respect to long-term benefit. The overall survival did not differ between GCD patients with and without PTCA, suggesting this treatment to be largely palliative. (ABSTR

Angioplasty, Balloon, Coronary↗
PubMed1997

Nitric oxide inhalation in the treatment of right ventricular dysfunction following left ventricular assist device implantation.

BACKGROUND: Following left ventricular assist device (LVAD) implantation in end-stage heart failure, the management of right ventricular dysfunction presents a therapeutic problem unresolved by conventional drug therapy (catecholamines, nitrates, and prostacyclin). This study was performed to investigate the effects of supplemental inhalation of nitric oxide (NO), a selective pulmonary vasodilator, postoperatively and prospectively. METHODS AND RESULTS: Intraindividual dose titration of NO was performed (0 to 40 ppm) according to a standardized protocol. Thereafter treatment was continued with the individually most effective dose of NO (25 to 40 ppm). In 8 consecutive male patients presenting with right ventricular dysfunction postoperatively, a significant dose-dependent improvement in hemodynamic function was observed: pulmonary vascular resistance decreased from 336+/-110 to 210+/-59 dynes x s x cm(-5) (P<.0001), cardiac index rose from 2.0+/-0.4 to 2.7+/-0.4 L x min(-1) x m(-2) (P<.003) at 40 ppm; doses of >20 ppm were effective in increasing cardiac index (P<.05). With continuous NO inhalation up to 48 hours, pulmonary vascular resistance decreased further to 155+/-33 dynes x s x cm(-5) (P<.0001) as the cardiac index increased to 3.3+/-0.6 L x min(-1) x m(-2) (P<.003). Pulmonary artery pressure decreased (P<.0001) as did systemic vascular resistance with hemodynamic improvement (P<.01). Central venous pressure and mean arterial pressure remained unchanged. Right ventricular ejection fraction at transesophageal echocardiography increased from 24+/-7% to 44+/-7% (P<.01) at the end of the study, and right ventricular end-diastolic volume decreased (P<.05). Weaning from NO therapy was successful at 2 to 8 days, and all patients were extubated. Right ventricular function remained stable thereafter. CONCLUSIONS: In the treatment of right ventricular dysfunction following LVAD implantation, inhalation of NO markedly decreased right ventricular afterload by its selective vasodilating effects on the pulmonary circulation without producing systemic hypotension; this merits further evaluation.

Administration, Inhalation↗