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Dan Aravot

Publications and source records attributed to Dan Aravot.

17 recordsLinked to original sources
PubMed2006

Pulmonary venous drainage through a highly vascularized left atrial tumor.

We present a patient with symptomatic congestive heart failure due to a left atrial sarcoma infiltrating and apparently occluding the left pulmonary veins. The tumor was highly vascularized and enabled attenuated blood drainage from the left upper and lower pulmonary veins despite intra-operative appearance as completely obliterative, thus avoiding persistent left lung pulmonary edema. The tumor was partially removed and the pathologic findings showed advanced angiogenesis. Malignant tumors may occlude large blood vessels and thus may result in the development of a collateral flow. However, we suggest that highly vascularized tumors (macroscopic totally occlusive) may serve as a sponge and enable attenuated blood flow through the tumor and hence may avoid a complete cut off in blood supply or drainage.

Aged, 80 and over↗
PubMed2006

Behçet's aortitis mimicking aortic valve endocarditis with subaortic complications.

Behçet's disease is a systemic inflammatory disease with rare cardiac involvement. We present a case of Behçet's aortitis involving the aortic and mitral valves with vegetations resembling aortic valve endocarditis with subaortic complications. Recurrent aortitis after aortic valve replacement resulted in an aortic pseudoaneurysm formation with moderate perivalvular aortic regurgitation that stabilized with immunosuppressive therapy and without the need for additional cardiac operation.

Adult↗
PubMed2005

Multiple arterial revascularization using the tangential K-graft technique.

The tangential K graft is a comfortable surgical technique aiming to increase cardiac surgeons' versatility in performing multiple arterial grafting using only two arterial conduits. One end of the free graft--either the right internal thoracic artery (RITA) or the radial artery (RA)--is attached to a marginal circumflex branch. Its other end is anastomosed end to side to a diagonal branch. After the left internal thoracic artery (LITA) is attached to the left anterior descending coronary artery, a wide-open side-to-side LITA to free RITA or RA anastomosis--resembling the letter K--is constructed.

Aged↗
PubMed2004

A bridge between hearts: mutual organ donation by Arabs and Jews in Israel.

BACKGROUND: The availability of organ transplants depends largely on the will of the donor families. Given the current state of affairs in Israel, the authors evaluated the stance of Jews and Arabs toward mutual organ donations. METHODS: Between October 1997 and December 1999, there were 4.8 million Jews and 1.09 million Arabs living in Israel. Data gathered from 22 general hospitals for this period yielded 373 potential organ donors and 171 families (45.8%) that consented to the procedure. Actual donation was obtained from 157 patients. The authors examined the characteristics of the potential organ donors and organ recipients and the reasons (religious and nonreligious) for familial consent or refusal. Donation made since onset of the Intifada (armed Palestinian resistance) was also reviewed to determine whether any changes took place. RESULTS: Consent was obtained from 48.9% of the Jewish families approached, 30.7% of the Muslim Arabs, and 66.6% of the Christian Arabs. For the whole sample, altruism was the main reason for consenting. The percentages of Arabs and Jews (per population) on the waiting list for a heart (Jews, 90%; Arabs, 10%) or liver (Jews, 78.66%; Arabs, 21.34%) and who received a heart (Jews, 90%; Arabs, 10%) or liver (Jews, 78.36%; Arabs, 21.64%) were similar. There were relatively more Arab recipients of kidney transplants (waiting list, 11%; recipients, 18.6%) because of the higher percentage of children in the Arab group who were given priority. Since September 2000 (start of the Intifada), there has been a trend toward an increasing rate of refusal to donate among Arabs (consent obtained in 52.9% of Jewish families approached vs. 27.9% of the Muslim Arabs), mainly because of fear of rejection by the community for cooperating with Jews. CONCLUSIONS: The rate of organ donations among Arabs and Jews in Israel is proportional to their representation in the general population. The main reason for donating organs is altruism. Apparently, altruism cuts across the boundaries of religion and ethnic groups, even in a country where conflict prevails. We trust that progress in the international arena will bring the current cycle of violence to an end and allow humanitarian values to take preference over politics.

Adult↗
PubMed2004

Coenzyme Q10 in patients with end-stage heart failure awaiting cardiac transplantation: a randomized, placebo-controlled study.

BACKGROUND: The number of patients awaiting heart transplantation is increasing in proportion to the waiting period for a donor. Studies have shown that coenzyme Q10 (CoQ10) has a beneficial effect on patients with heart failure. HYPOTHESIS: The purpose of the present double-blind, placebo-controlled, randomized study was to assess the effect of CoQ10 on patients with end-stage heart failure and to determine if CoQ10 can improve the pharmacological bridge to heart transplantation. METHODS: A prospective double-blind design was used. Thirty-two patients with end-stage heart failure awaiting heart transplantation were randomly allocated to receive either 60 mg U/day of Ultrasome--CoQ10 (special preparation to increase intestinal absorption) or placebo for 3 months. All patients continued their regular medication regimen. Assessments included anamnesis with an extended questionnaire based partially on the Minnesota Living with Heart Failure Questionnaire, 6-min walk test, blood tests for atrial natriuretic factor (ANF) and tumor necrosis factor (TNF), and echocardiography. RESULTS: Twenty-seven patients completed the study. The study group showed significant improvement in the 6-min walk test and a decrease in dyspnea, New York Heart Association (NYHA) classification, nocturia, and fatigue. No significant changes were noted after 3 months of treatment in echocardiography parameters (dimensions and contractility of cardiac chambers) or ANF and TNF blood levels. CONCLUSIONS: The administration of CoQ10 to heart transplant candidates led to a significant improvement in functional status, clinical symptoms, and quality of life. However, there were no objective changes in echo measurements or ANF and TNF blood levels. Coenzyme Q10 may serve as an optional addition to the pharmacologic armamentarium of patients with end-stage heart failure. The apparent discrepancy between significant clinical improvement and unchanged cardiac status requires further investigation.

Adult↗
PubMed2004

Bicoherence analysis of new cardiovascular spectral components observed in heart-transplant patients: statistical approach for bicoherence thresholding.

Following heart transplant (HT), the patient's heart functions under complete cardiac denervation. As a result, the variability in physiologic signals is extremely reduced. We have previously reported that in addition to the typical spectral components (of very low amplitude), part of the HT patients (above 50%) demonstrated unexpected additional peaks in their heart rate and blood pressure spectra. These peaks may be a result of the development of compensatory mechanism induced by loss of parasympathetic control, or of increased importance of nonlinear control interactions. It is important to quantify these strange, unexpected very-high frequency (VHF) peaks, to understand their origin and their contribution to cardiac control in transplant patients. In this paper, we chose to examine these VHF peaks by applying the bicoherence approach. The reduced signal to noise ratio, occurring in these patients, results, however, in an extremely noisy bicoherence. We, therefore, developed several statistical tools in order to distinguish between "true" bicoherence peaks (reflecting true phase coupling) and spurious peaks. The outcome of these methods was an efficient and sensitive bicoherence thresholding procedure, able to identify most of the spurious peaks. Applying these tools to the bicoherence of cardiovascular signals which display VHF peaks, revealed several significant bicoherence peaks. Interestingly, these peaks consisted of two different types. The first type of VHF peaks simply reflects nonlinear cardiac-respiratory coupling, imposed by nonsinusoidal breathing. The second type, however, is clearly not induced by the respiratory system. We believe that these type-2 VHF peaks reflect the evolution of a new, yet unexplained, compensatory mechanism.

Adult↗
PubMed2004

[Lung and heart-lung transplantation in Rabin medical center: early experience with 70 cases].

Lung transplantation is a relatively new field in solid organ transplantation. We present our early experience with the first 70 cases at the Rabin Medical Center during the years 1997-2003. Forty seven patients underwent single lung, eight double lung and eight heart-lung transplantations. The patients treated included 49 men and 21 women aged 5-66 years. There were 26 cases with emphysema COPD. 30 patients with pulmonary fibrosis. 5 patients with pulmonary hypertension/Eisenmenger and 9 patients with cystic fibrosis and bronchiectasis. Although early results (1997-1999) showed 1 and 3 year survival of only 50%, in the last 3 years (2000-2003), survival reached 84% and 82% at 1 and 3 years respectively. Improvement in the success rate is due to better patient selection, new immunosuppressive regimen and, most importantly, excellent teamwork. We conclude that lung transplantation is a viable option for selected patients with end-stage lung disease.

Adolescent↗
PubMed2003

Degrees of severe stenoses in sigma-shaped versus C-shaped right coronary arteries.

The right coronary artery (RCA) appears either C-shaped or sigma-shaped during standard angiography. The purpose of the present investigation was to assess whether C-shaped RCAs are associated with more atherosclerotic disease than sigma-shaped RCAs. The study sample comprised 120 consecutive patients who underwent coronary catheterization and multivariate analysis was conducted using several systemic risk factors for atherosclerosis. The proportion of sigma-shaped RCAs found in a group whose angiograms showed little or no obstruction (70%) was significantly higher than that found in the group with significant obstruction (33%, p <0.001). In conclusion, a C-shaped RCA is associated with atherosclerosis.

Adult↗
PubMed2003

Late-onset chylothorax after heart-lung transplantation.

Chylothorax has rarely been reported after heart and lung transplantation. We describe a case of a bilateral chylothorax that occurred in a 53-year-old man 4 months after heart-lung transplantation and review the three additional reports in the literature of chylothorax after heart transplantation. Chyle drainage may cause compromise of the transplant patient. The good nutritional status of our recipient, however, allowed conservative therapy with chest tube drainage and enteral low-fat diet, without the need for surgical intervention. We concluded that chylothorax can presents late after lung transplantation and that conservative treatment should be considered in patients with good nutritional status.

Chylothorax↗
PubMed2003

Tricuspid valve papillary fibroelastoma: an unusual cause of intermittent dyspnea.

A 67-year-old woman was referred for investigation of intermittent dyspnea, which was known for years but had been worsening over the previous 3 months. Two-dimensional echocardiography revealed the presence of a mass attached to the anterior leaflet of the tricuspid valve. The patient was successfully operated on to excise the right atrial mass and preserve the tricuspid apparatus. Morphological examination of the excised tissue led to the diagnosis of papillary fibroelastoma. Surgical treatment should be considered when such a tumor is diagnosed, even in asymptomatic patients, because of the possible risk of embolization.

Aged↗
PubMed2003

Late postoperative pleural effusion following lung transplantation: characteristics and clinical implications.

OBJECTIVE: Pleural effusions are extremely common in the early postoperative period after lung transplantation (LTX). It occurs in all transplant recipients, and like pleural fluid following other cardiothoracic surgery is bloody, exudative and neutrophil predominant. There was no information, however, on the characteristics of the late (14-45 days) postoperative pleural fluid after LTX. The purpose of this study was to describe the characteristics and the clinical implications of late postoperative pleural effusion after LTX. METHODS: Thirty-five patients underwent TX between May 1997 and May 2001. Seven patients (20%) developed late postoperative pleural effusion. Thoracentesis were performed in these patients and the white blood cell counts, cell differential as well as biochemical parameters were determined. RESULTS: The median time for late pleural effusion appearance was 23 days (range, 14-34 days) after TX. The pleural effusions were medium in size (700 ml, range, 100-1300), exudative in all the patients and had lymphocyte predominance. No evidence of fluid recurrence or clinical deterioration was noted in these patients. CONCLUSION: Late-onset exudative lymphocytic pleural effusion after LTX is not uncommon. When there is no evidence of rejection or infection, it usually has a benign, favorable outcome.

Adult↗
PubMed2002

Functional restitution of cardiac control in heart transplant patients.

Cardiovascular control is fundamentally altered after heart transplantation (HT) because of surgical denervation of the heart. The main goal of this work was the noninvasive characterization of cardiac rate control mechanisms after HT and the understanding of their nature. We obtained 25 recordings from 13 male HT patients [age = 28-68 yr, time after transplant (TAT) = 0.5-62.5 mo]. The control group included 14 healthy men (age = 28-59 yr). Electrocardiogram, continuous blood pressure (BP), and respiration were recorded for 45 min in the supine position and then during active change of posture (CP) to standing. The signals were analyzed in the time domain [mean and variance of heart rate (HR) and rise time of HR in response to CP] and the frequency domain [low and high frequency (LF and HF)]. Our principal finding was the consistent pattern of evolution of the HR response to standing: from no response, via a slow response (>40 s, TAT > 6 wk), to a fast increase (<20 s, TAT > 24 mo). HR response correlated with TAT (P < 0.001). LF correlated with HR response to CP (P < 0.0001); HF and HR did not. An important finding was the presence of very-high-frequency peaks in the power spectrum of HR and BP fluctuations. Extensive arrhythmias tended to appear at the TAT that corresponds to the transition from slow to fast HR response to CP. Our results indicate a biphasic evolution in cardiac control mechanisms from lack of control to a first-order control loop followed by partial sympathetic reinnervation and, finally, the direct effect of the old sinoatrial node on the pacemaker cell of the new sinoatrial node. There was no indication of vagal reinnervation.

Adult↗
PubMed2002

Serum concentrations of leptin in heart, liver and kidney transplant recipients.

BACKGROUND: Leptin is a 16 kDa hormone synthesized by adipocytes and involved in body weight regulation. OBJECTIVES: To determine serum leptin concentrations in heart, liver and kidney transplant recipients. METHODS: We investigated 57 patients: 18 male heart transplant recipients (age 25-69 years) at 1-66 months after transplantation, 6 female and 8 male liver transplant recipients (age 33-70) at 11-73 months after transplantation, and 10 female and 15 male kidney transplant recipients (age 20-61) at 3-138 months after transplantation. All recipients were receiving immunosuppressive therapy, including prednisone 0-20 mg/day, azathioprine 75-125 mg/day, cyclosporin 100-250 mg/day or tacrolimus 2-10 mg/day. The results were compared to those of 10 female and 10 male healthy controls. Morning serum concentrations of leptin were measured with a commercial radioimmunoassay (Linco Research Inc., USA), and serum insulin and cortisol levels were measured by radioimmunoassay. RESULTS: Patients (both men and women) after heart, liver and kidney transplantation exhibited significantly higher serum concentrations of leptin and leptin/body mass index ratios than controls. Serum leptin concentrations were significantly higher in women than in men and correlated very significantly with BMI in all cases. The multivariate stepwise analyses showed that among parameters including BMI, gender, age, time after transplantation, prednisone dose, hematocrit, serum concentrations of glucose, albumin, creatinine, cortisol and insulin, only BMI, gender, cortisol and insulin were significant independent determinants of serum leptin levels in these patients. CONCLUSIONS: This is the first report showing that, in addition to body mass index and gender, basal cortisol and insulin levels affect the hyperleptinemia in transplant patients. The clinical relevance of hyperleptinemia in these patients will require further investigation.

Adult↗
PubMed2002

Continuous intravenous epoprostenol in pulmonary hypertension: the Israel experience.

BACKGROUND: Primary idiopathic pulmonary hypertension is a rapidly progressive disease with a median survival of less than 3 years. Recently its prognosis was shown to dramatically improve with the use of epoprostenol, an arachidonic acid metabolite produced by the vascular endothelium, which increases the cardiac output and decreases the pulmonary vascular resistance and pulmonary arterial pressure. This drug enhances the quality of life, increases survival and delays or eliminates the need for transplantation. OBJECTIVE: To review the experience of Israel hospitals with the use of epoprostenol. METHODS: The study group comprised 13 patients, 5 men and 8 women, with an age range of 3-53 years. All patients suffered from arterial pulmonary hypertension. Epoprostenol was administered through a central line in an increased dose during the first 3 months, after which the dose was adjusted according to the clinical syndrome and the hemodynamic parameters. RESULTS: After 3 months the mean dose was 10 ng/kg/min and the pulmonary artery pressure decreased from 7 to 38%. After one year, the PAP decreased at a slower rate. Two cases required transplantation, three patients died, and seven continued taking the drug (one of whom discontinued). Four episodes of septicemia were observed. Today 10 patients are alive and well and 7 continue to take epoprostenol. CONCLUSION: We found that epoprostenol improves survival, quality of life and hemodynamic parameters, with minimum side effects.

Adolescent↗
PubMed2002

The effect of donor age on survival after lung transplantation.

BACKGROUND: Historically, donor age above 55 years has been considered to be a relative contraindication for organ transplantation. The shortage of organs for transplantation has led to the expansion of the donor pool by accepling older donors. OBJECTIVES: To compare the 1 year follow-up in patients after lung transplantation from older donors (> 50 years old) and in patients after transplantation from younger donors (< or = 50 years). METHODS: The study group comprised all adult patients who underwent lung transplantation at the Rabin Medical Center between May 1997 and August 2001. Donors were classified into two groups according to their age: < or = 50 years (n = 20) and > 50 years (n = 9). Survival, number and total days of hospitalization, development of bronchiolitis obliterans syndrome, and pulmonary function tests, were examined 1 year after transplantation. RESULTS: We performed 29 lung transplantations in our center during the observed period. Donor age had no statistically significant impact on 1 year survival after lung transplantation. There was no statistically significant effect on lung function parameters, the incidence of hospitalization or the incidence of bronchiolitis obliterans between both donor age groups at 1 year after transplantation. CONCLUSIONS: Donor age did not influence survival or important secondary end-points 1 year after lung transplantation By liberalizing donor criteria of age up to 65 years, we can expand the donor pool, while assessing other possible mechanisms to increase donor availability.

Adult↗
PubMedDate not supplied

Heart rate variability in patients with major depression.

This study compared cardiac autonomic modulation in physically healthy patients with major depressive disorder to that in mentally healthy heart transplant recipients and physically and mentally healthy comparison subjects by using a nonlinear measure and a conventional measure of heart rate variability. No significant differences in cardiac autonomic modulation were noted between the depressive group and the transplant recipients, but both of those groups had significantly lower mean values for heart rate variability measures relative to the healthy comparison subjects. The results support the hypothesis that cardiac autonomic imbalance (reduced vagal modulation) to the extent of cardiac neuropathy is present in depression.

Algorithms↗