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R J Novick

Publications and source records attributed to R J Novick.

At least 91 records · Page 5Linked to original sources
PubMed1984

Differential electrical activity of the atria during cardioplegic arrest in pigs.

To elucidate the electrical interrelationship of the atria during cardioplegic arrest, simultaneous bipolar right atrial (RA) and left atrial (LA) electrograms and myocardial temperatures of all four chambers of the heart were recorded in 10 pigs during an hour of aortic clamping. Five pigs (Group 1) underwent single venous cannulation; in 5 others (Group 2), snared double caval cannulation, RA venting, and intracavitary RA irrigation with cold saline solution were employed. Myocardial protection was provided by systemic hypothermia (28 degrees C) and intermittent intraaortic administration of cold (4 degrees C) hyperkalemic (20 mEq/L) crystalloid cardioplegic solution. Single RA cannulation was associated with sustained RA activity during cardioplegic arrest and with the warmest mean myocardial temperatures. Electrical activity was infrequent in the left atrium, which was often silent while RA impulses continued to be observed. Four Group 1 pigs exhibited high-grade RA-LA block, whereas in 2 animals completely asynchronous RA-LA electrical activity occurred. Isolated LA activity was not encountered. The combined methods used in Group 2 pigs significantly reduced mean myocardial temperatures. Both RA and LA impulses were practically abolished, and their mean durations decreased 96% and 85%, respectively. It is concluded that the pattern of electrical activity differs in the two atria during cardioplegic arrest when a single venous cannula is employed. Intracavitary RA irrigation with cold saline solution in the presence of snared caval cannulas provides improved myocardial hypothermia and effectively eliminates both RA and LA activity in the course of cold crystalloid cardioplegia.

Animals↗
PubMed1984

Surgery for postinfarction left ventricular aneurysm: prognosis and long-term follow-up.

To identify preoperative indicators of outcome following surgery for postinfarction left ventricular aneurysm, the authors have analysed the clinical course of 67 consecutive patients who underwent operation from 1970 to 1982. Follow-up extended to 12 years (mean 4.6 years) and was 97% complete. Postoperative mortality was 8.9%. Factors that were associated with a significantly (p less than 0.05) increased risk of early death included emergency surgery, the presence of ventricular arrhythmias preoperatively and a left ventricular end-diastolic pressure of more than 25 mm Hg on cardiac catheterization. Patients who underwent myocardial revascularization concomitantly had a lower mortality (7.1% v. 18.2% for aneurysmectomy alone), decreased postoperative morbidity and increased longevity. Marked functional improvement was noted in all groups. Actuarial survival (including operative mortality) was 66% at 6 years, and was significantly (p less than 0.05) better in patients operated upon for angina (83.6% +/- 8.1%) than in those operated upon for congestive heart failure (53% +/- 13%). The authors conclude that the most important predictor of outcome following postinfarction aneurysm surgery is the preoperative hemodynamic status of the left ventricle. Since functional recovery and prognosis after operation have been excellent, an aggressive surgical approach to symptomatic left ventricular aneurysms is warranted.

Adult↗
PubMed1984

Reaction of subcutaneous tissues to injection of Fluosol-DA, 20%.

To study the extent of tissue reaction, the blood substitute Fluosol-DA, 20%, blood, normal saline and doxorubicin (Adriamycin) were injected in equal amounts into the subcutaneous tissues of four separate regions of the dorsum of seven rats. The animals were sacrificed at 6, 12, 24 and 48 hours, and at 1, 2 and 6 weeks after injection. The injected areas were examined by light and electron microscopy and the reaction was graded semiquantitatively. Results indicated the following: (a) saline, as expected, produced only mild inflammation that quickly resolved; (b) blood caused a hematoma with recognizable erythrocytes for 7 days and by 14 days hemosiderin-laden macrophages and fibrosis were present; (c) Adriamycin caused necrotizing lesions that were delayed for 24 hours, were severe at 2 and 7 days, and caused the disappearance of the muscle layer by 14 days and (d) Fluosol-DA caused the appearance of foamy macrophages at 12 hours that persisted until at least 2 weeks after injection. The authors conclude that Fluosol-DA, 20%, is not inert and causes a characteristic inflammatory response when injected subcutaneously. Whether a clinically important problem from subcutaneous infiltration of Fluosol could arise, for example, around a peripheral intravenous catheter, has yet to be determined. At present, it is probably safer to administer this drug through a central vein.

Animals↗
PubMed1984

Toward a better understanding of the hemodynamic effects of protamine and heparin interaction.

Hemodynamic changes have been documented during protamine infusion into heparinized but not unheparinized pigs and suggest that a protamine-heparin interaction might be responsible. This hypothesis was tested in four groups of pigs by varying the dosage and order of administration of these two drugs: Group I (n = 9) received heparin (3 mg/kg) followed by protamine (3 mg/kg); Group II (n = 9) received protamine (3 mg/kg) followed by heparin (3 mg/kg); Group III (n = 9) received protamine (25 mg/kg) followed by heparin (3 mg/kg); and Group IV (n = 16) received protamine-heparin complex (protamine 3 mg/kg and heparin 3 mg/kg mixed immediately prior to injection). Systemic and pulmonary arterial pressures, systemic and pulmonary vascular resistances, left ventricular end-diastolic pressure, central venous pressure, cardiac output, and heart rate were measured before and at 1.0, 2.5, 5.0, and 15 minutes after protamine, heparin, or protamine-heparin complex infusions. Immediately following protamine infusion, Group I pigs exhibited transiently but significantly increased pulmonary artery pressure, pulmonary vascular resistance, systemic vascular resistance, and central venous pressure and decreased cardiac output with (Group Ib, n = 5) or without (Group Ia, n = 4) systemic hypotension. The fact that no hemodynamic changes occurred in Group II confirms that infusion of clinical doses of protamine produces no hemodynamic changes in unheparinized pigs. Protamine alone in high doses (Group III) produced hemodynamic changes similar to clinical-dose protamine reversal of heparin (Group I). This effect suggests that the presence of heparin in the circulation lowers the threshold for protamine-mediated hemodynamic responses. Infusion of heparin (3 mg/kg) into pigs 15 minutes after treatment with high (25 mg/kg) (Group III) but not clinical (3 mg/kg) (Group II) doses of protamine produced hemodynamic effects similar to clinical-dose protamine reversal of heparin (Group I), suggesting that a protamine-heparin interaction may be responsible. These results also suggest a rapid inactivation in vivo of clinical doses (3 mg/kg) (Group II) of infused protamine. Protamine-heparin complex formed in vitro (Group IV) also produced hemodynamic changes similar to clinical-dose protamine reversal of heparin (Group I), suggesting that formation of this complex in vivo may be the protamine-heparin interaction responsible. Protamine-heparin complex may well be a useful tool in further elucidating the full effects of protamine reversal of heparin.

Animals↗
PubMed1983

Atrial electrical activity and its suppression during cardioplegic arrest in pigs.

Right atrial electrical activity and myocardial temperatures of all four chambers were monitored during a 1 hour period of cardioplegic arrest in 20 pigs subjected to different methods of venous cannulation and cardiac cooling. Myocardial protection was provided by systemic hypothermia (28 degrees C) and intermittent intra-aortic administration of cold (4 degrees C) hyperkalemic (20 mEq/L) crystalloid cardioplegia. The use of a single right atrial cannula for venous drainage was associated with sustained atrial activity (50 +/- 5.5 minutes) during cardioplegic arrest and the warmest right atrial (27 degrees +/- 0.2 degrees C) and right ventricular (20.5 degrees +/- 0.4 degrees C) temperatures. Separate caval cannulation with snaring and right atrial venting decreased right atrial and ventricular temperatures marginally (25.3 degrees +/- 0.5 degrees C and 19.1 degrees +/- 0.4 degrees C, respectively, p less than 0.05) but did not significantly alter the duration of atrial electrical activity (42.2 +/- 2.5 minutes, p greater than 0.05). Addition of an extracavitary right atrial drip of cold (4 degrees C) saline, 750 ml for the 1 hour aortic clamping period, reduced right atrial temperature (22.8 degrees +/- 0.4 degrees C) and activity (24.8 +/- 6.3 minutes) to a significant extent. Intracavitary irrigation of the right atrium with cold saline, in the presence of snared double caval cannulas, decreased right atrial and ventricular temperatures most dramatically (17.0 degrees +/- 0.5 degrees C and 17.5 degrees +/- 0.3 degrees C, respectively, p less than 0.05), reduced the duration of atrial electrical activity by 84% (to 8 +/- 3.9 minutes, p less than 0.01), and diminished the total number of atrial contractions per hour of aortic clamping by 88%. It is concluded that intracavitary right atrial cooling with separate snared caval cannulation is the most effective method of ensuring atrial inactivity and prolonged right heart hypothermia during cardioplegic arrest.

Animals↗
PubMedDate not supplied

The learning curve of an academic cardiac surgeon: use of the CUSUM method.

BACKGROUND: Despite the sizeable volume of research on the determinants of outcome after cardiac operations, few articles have analyzed the learning curves of individual cardiac surgeons over time. The objective of our study was to analyze statistically the learning curve of an academic cardiac surgeon in reducing operative morbidity and mortality during a 10-year interval. METHODS: The study cohort of 1347 consecutive and unselected patients undergoing cardiac surgical operations from October 1988 to September 1998 were grouped into five 2-year blocks (periods 1 to 5) according to the date of operation. The main outcome measures were operative mortality rate and standardized definitions of perioperative myocardial infarction, intra-aortic balloon pump use, reoperation for bleeding, stroke, sternal wound complications, sepsis, and respiratory insufficiency. Preoperative risk factors and operative results in periods 1 to 5 were compared statistically using a chi-square test for linear trend (categorical variables) or analysis of variance with linear contrast and lack of fit tests (continuous variables). In addition, the cumulative sum (CUSUM) method was used to determine the association among operative morbidity, mortality, and prespecified 80% alert and 95% alarm boundary lines in practice years 1, 5, and 9. RESULTS: Of the preoperative risk factors, only patient age showed an important change during the 10 years of the study (61.3+/-0.7 to 64.3+/-0.6, p = 0.001). There were no statistically significant changes from periods 1 to 5 in overall operative mortality (4.0% to 2.2%, p = 0.56) or in the rates of perioperative stroke (1.8% to 3.8%, p = 0.33), sternal wound complications (0.4% to 0.8%, p = 0.97), sepsis (0.9% to 0.8%, p = 0.63), or respiratory failure (4.4% to 2.8%, p = 0.21). Decreases occurred in a linear fashion during periods 1 to 5 in mortality after coronary artery bypass grafting (5.1% to 1.3%, p = 0.012) and in the rates of perioperative myocardial infarction (7.0% to 2.2%, p = 0.005), intra-aortic balloon pump use (7.0% to 3.0%, p = 0.05), and reoperation for bleeding (8.4% to 2.2%, p = 0.001). The number of uneventful cases between a death or complication increased from 2.82+/-0.43 in period 1 to 6.44+/-1.10 in period 5 (p < 0.001). On CUSUM analysis, the cumulative failure rate in year 1 transgressed the upper 80% alert line after 56 cases and the upper 95% alarm line after 69 cases. During years 5 and 9 the failure rate gravitated around the 80% and 95% "reassurance" lines, respectively, indicating improved results as compared to year 1. CONCLUSIONS: The mortality rate after coronary artery bypass grafting and select perioperative morbidity rates improved in a linear fashion from the onset of independent practice to year 10. The CUSUM method was helpful in identifying suboptimal results during the first year of practice and shows promise as a method of prospective quality control in cardiac surgery. These data support mentorship of new consultants by a senior surgeon during the first year or two of independent practice.

Adult↗
PubMedDate not supplied

New trends in lung preservation: a collective review.

Since the last review on lung preservation in 1985, enormous progress has been made in experimental and clinical lung transplantation. This comprehensive review examines recent advances in the experimental laboratory in optimizing conditions during organ procurement, lung storage, and reperfusion to minimize ischemia-reperfusion injury in lung allografts.

Animals↗
PubMedDate not supplied

A prospective randomized controlled trial of initial immunosuppression with ALG versus OKT3 in recipients of cardiac allografts.

Thirty-nine heart transplant recipients were randomized prospectively to receive OKT3 or antilymphoblast globulin (ALG) for 7 days, having otherwise identical protocols (group 1: OKT3, n = 20 patients; group 2: ALG, n = 19 patients). No preoperative immunosuppression was given. The protocol consisted of methylprednisolone, 500 mg intraoperatively, followed by 1 mg/kg/day, intravenously or orally, tapering to 0.2 mg/kg/day at 1 month; oral cyclosporine starting 3 to 5 days after transplantation; selective use of azathioprine, 1 to 4 mg/kg/day; and either OKT3, 5 mg/day for 7 days, or ALG, 15 mg/kg/day for 7 days. Of the 39 patients in the study, 34 are alive 6 months to 2 years after transplantation. The actuarial survival at 2 years for the OKT3 and ALG groups was 92% (+/- 0.07%) and 83% (+/- 0.09%), respectively (not significant [NS]). The time to first rejection for group 1 was 5.6 weeks and for group 2 was 5.3 weeks (NS). The mean number of rejections for group 1 and group 2 was 2.1 episodes per patient and 1.4 per patient, respectively (NS). Three patients in each group were free of rejection at 6 months. The total number of infections at 6 months was 1.05 per patient in group 1, 0.74 per patient in group 2 (NS), with 35% of patients receiving OKT3 and 52% of patients receiving ALG actuarially free of infection by 6 months after surgery (NS). During the first 24 hours after surgery, no significant differences were noted in mean blood pressure, central venous pressure, or Po2 between the groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗
PubMedDate not supplied

Reduced incidence of severe infection after heart transplantation with low-intensity immunosuppression.

Despite advances in immunosuppressive therapy and prolonged graft and patient survival, infection after heart transplantation remains problematic. From January 1987 through June 1989, 104 heart transplantations were performed in 100 patients. Immunosuppression induction was by antilymphocyte globulin for 7 days, with oral cyclosporine introduced on stabilization of kidney function (day 3). Steroid therapy was rapidly tapered, and azathioprine was added only in cases of positive donor crossmatch or steroid-resistant rejection. No reverse isolation was used. Twenty-two deaths occurred, one from sepsis. Actuarial survival at 6 months, at 1 year, and at 2 years was 85% +/- 4%, 81% +/- 3%, and 75% +/- 4%, respectively. Fifty-four patients had 81 infections, of which 21 were bacterial; 83% of these episodes were treated. Sixty infections were opportunistic (85% viral), and only 23% necessitated treatment. Actuarial infection-free rates (all types necessitating treatment) at 1 month, at 6 months, and at 2 years were 83% +/- 4%, 75% +/- 5%, and 75% +/- 5%, respectively. Of the 100 transplant recipients, 66% were treated with azathioprine; 47 patients (69%) had an infection, whereas only seven (19%) of the patients not receiving azathioprine became infected (p less than 0.00001). Rejection was noted in 66% of patients, with a median time to the first episode of 4 weeks. A low-intensity immunosuppressive regimen has resulted in fewer serious infections, with acceptable graft loss from rejection. Increased infection surveillance is required for the first 30 days postoperatively and after treatment of rejection episodes.

Actuarial Analysis↗
PubMedDate not supplied

Extending cardiac allograft ischemic time and donor age: effect on survival and long-term cardiac function.

Of 219 heart transplant patients with follow up for at least 3 months after transplantation, cardiac allograft ischemic time was more than 4 hours in 28% and more than 5 hours in 10%. In 1988 and 1989 grafts with ischemic times longer than 4 hours were used in 44% and 45% of cases, respectively. Overall, donor age has been 35 or more years in 22% and 45 or more in 9%. In 1989 donor age was 35 or more years in 39% of cases and 45 or more in 18%. Fifteen of 20 grafts from donors 45 years or older were used for patients aged 50 or older. There was no relationship between donor age or ischemic time and 90-day graft loss. At 3 and 12 months, cardiac function, assessed by treadmill exercise duration, radionuclide angiography, and rest and peak supine exercise hemodynamics, was also unrelated to donor age or ischemic time. Therefore by careful selection of appropriate donors, extending both graft ischemic time and donor age has increased the potential donor pool and has not to date been associated with increased graft loss or adverse effects on cardiac function 3 months and 1 year after heart transplantation.

Adult↗
PubMedDate not supplied

Successful use of the "unacceptable" heart donor.

Chronic shortage of donor organs has heightened interest in new strategies for increasing donor availability. Unacceptable hearts for transplant have previously been characterized by donor age greater than 40 years, more than 20% donor/recipient weight mismatch, ischemic time more than 4 hours, and the presence of coronary artery disease. A series of 185 consecutive orthotopic heart transplants were retrospectively examined. A significant number of donor hearts used were unacceptable by one or more of the above criteria. Our current approach is to match donors to recipients using a wide range of criteria. Donors are now accepted from any location in North America. We have accepted donors more than 55 years of age and donors weighing less than 50% of the recipient's body weight. Because of the chronic shortage of donor organs, donor criteria have been effectively liberalized, thereby increasing the donor pool without compromising the overall results of heart transplantation.

Actuarial Analysis↗
PubMedDate not supplied

Should heart-lung transplant donors and recipients be matched according to cytomegalovirus serologic status?

Cytomegalovirus (CMV) infection is a major cause of morbidity and mortality after heart-lung transplantation. Primary CMV infections in previously seronegative recipients are more severe than reactivated or reinfections in seropositive patients, and this has led to a policy of obligatory donor-recipient CMV matching in several centers performing heart-lung transplantation. Of our 13 heart-lung transplants, three were done in CMV-seronegative patients who received CMV-positive grafts. The first patient did not seroconvert and exhibited no evidence of CMV infection despite close follow-up extending to almost 2 years. In the second patient, who required augmented immunosuppression because of recurrent lung rejection early postoperatively, fulminating CMV pneumonitis developed, which was ultimately controlled with ganciclovir and high-dose CMV immune globulin. As an outpatient, she is currently receiving ganciclovir maintenance therapy. The third patient, who received high-dose CMV immune globulin prophylaxis, had CMV isolated from her bronchoalveolar lavage fluid, as well as from urine, but remains clinically well 5 months after receiving her transplant. We conclude that the matching of donors and recipients for CMV serologic status is desirable, but not essential, before heart-lung transplantation. CMV immune globulin prophylaxis may be effective in preventing clinical CMV disease in patients receiving a CMV-mismatched graft, and severe CMV pneumonitis may be effectively treated by a combination of ganciclovir and high-dose CMV immune globulin therapy.

Adult↗
PubMedDate not supplied

Special considerations for heart transplantation in congenital heart disease. The Paediatric Heart Transplant Group.

Congenital heart disease as an indication for heart transplantation accounts for a small number of the total heart transplant experience--less than 3% in most centers. We have performed heart transplantation in eight such patients, accounting for 4% of our total experience. All these patients had specific anatomic anomalies relevant to transplantation. None had morbidity directly related to their anatomic defect and subsequent transplant. Six of the eight had undergone no prior palliative or corrective repairs. One child had a left Blalock-Taussig shunt, and one had bilateral Glenn shunts and a Fontan repair. Technical considerations for orthotopic heart transplantation are described for transposition of the great arteries, left superior vena cava with and without bridging innominate vein, common atrium, presence of Blalock-Taussig shunt, bilateral Glenn shunts, and Fontan repair. Anatomic congenital heart disease is becoming a more frequent indication in heart transplantation. Heart transplantation in the presence of structural congenital heart disease may be technically challenging. Nevertheless, transplantation offers an effective therapeutic alternative for patients with end-stage congestive heart failure and congenital heart disease.

Adult↗
PubMedDate not supplied

Nontuberculous mycobacterial infections in heart transplant recipients: a seventeen-year experience.

A retrospective review was undertaken to determine the clinical features, outcome, and impact on survival of nontuberculous mycobacterial infections in 14 (of 502) heart transplant recipients. The prevalence of these infections was significantly higher (p less than 0.05) during the precyclosporine than during the cyclosporine era. The mean interval from transplantation to diagnosis was 3.5 +/- 0.7 years (+/- SEM). The 14 patients had a higher (p less than 0.05) linearized rejection rate than did other transplant patients during postoperative years 1, 2, and 4 to 6, and had received 7.3 +/- 2 gm of methylprednisolone as bolus treatment of rejection before diagnosis. Eight patients were initially seen with disseminated disease, four had localized pulmonary infection, one had subcutaneous infection in the previous site of a left ventricular assist device, and in one the organism was cultured from a fluid collection adjacent to a hip prosthesis. Twelve patients were first given 3 +/- 1 antimycobacterial drugs; the infections were usually controlled, but in 75% of patients the therapeutic regimen was prematurely stopped or altered because of drug toxicity. Mycobacterial infection was a contributory cause of death in only one patient. Actuarial survival in the 14 patients was not significantly different from the entire transplant population at 4 to 7 years. We conclude that nontuberculous mycobacterial infections occur late after heart transplantation, that drug treatment is usually successful (although difficult), and that long-term survival is not adversely affected if the infection is successfully controlled.

Adult↗
PubMedDate not supplied

Redo lung transplantation: a North American-European experience.

An international survey of redo lung transplantation was performed to identify the morbidity and mortality rates and factors correlating with increased or decreased survival after this procedure. Twenty institutions in North America and Europe participated, and the study cohort included 61 patients who underwent 63 redo lung transplantation operations. Patients undergoing a redo heart-lung transplantation were excluded. The indications for reoperation included obliterative bronchiolitis (32 patients), graft failure (14 patients), intractable airway problems (8 patients), severe acute lung rejection (5 patients), and miscellaneous complications (4 patients). Five types of retransplantation procedures were performed, including redo ipsilateral single lung transplantation (24 patients), redo contralateral single lung transplantation (11 patients), single lung transplantation after double lung or heart-lung transplantation (13 patients), redo double lung transplantation (8 patients), and double lung transplantation after a previous single lung transplantation (7 patients). Actuarial survival was 65%, 49%, 42%, 35%, and 32% at 1, 3, 6, 12, and 24 months, respectively; survival was significantly (p < 0.05) worse than that of first-time lung transplant recipients recorded in the International Society for Heart and Lung Transplantation Registry. Actuarial survival did not differ according to the original diagnosis of the recipients, the indication for reoperation, or the type of retransplantation procedure performed. Similarly, recipient cytomegalovirus status and ventilator status before reoperation did not affect postoperative survival. Trends toward an improved outcome were noted in patients who were ambulatory before reoperation and in those receiving an ABO identical, as opposed to ABO compatible, graft at reoperation. Life table and step-wise logistic regression analysis identified donor cytomegalovirus status at reoperation to be an important determinant of outcome, with significantly (p < 0.05) improved survival in the donor cytomegalovirus-negative group. Polymicrobial infection was the most common cause of death at all time intervals after reoperation. The presence of disseminated infection and established multiorgan failure was almost uniformly associated with a fatal outcome. We conclude that redo lung transplantation may be indicated only in well-selected patients with obliterative bronchiolitis, severe airway complications, or graft failure. Donor cytomegalovirus status at reoperation is an important predictor of survival. The presence of disseminated infection and established multiorgan failure should be contraindications to lung retransplantation.

Adolescent↗