Zaher S. Azzam

Septal/Free Wall Curvature Ratio: A Noninvasive Index of Pulmonary Arterial Pressure

The leftward septal shift, a well-recognized feature of pulmonary hypertension, was used to quantify right ventricular pressure in 16 patients with pulmonary hypertension and 11 control patients, all with normal left ventricular function. Pulmonary pressure was calculated from the tricuspid regurgitation jet and left ventricular pressure was taken by arm cuff measurements. Short-axis echocardiographic images were obtained and the midwall curvatures of the septum and the left ventricular free wall were measured for each frame from end diastole to end systole and averaged. The septal/free-wall curvature ratio (CR) was 0.37 +/- 0.19 in the study group compared with 0.79 +/- 0.06 in the control group (p < 0.0001). A tight relationship between the CR and the transseptal/transmural pressure ratio (CR = 0.057 + 0.89 x transseptal/transmural pressure ratio; r = 0.98; p < 0.001) was obtained by linear regression. Given the systolic arterial pressure, the pulmonary systolic pressure is given by: systolic arterial pressure x (1.064-1.12 x CR). Therefore the CR can be used as a noninvasive index that reflects the level of pulmonary pressure in relationship to the systolic arterial pressure.

Arterio-venous access in end-stage renal disease patients and pulmonary hypertension

Background: The syndrome of pulmonary hypertension (PHT) in end-stage renal disease (ESRD) has been described in patients on chronic hemodialysis (HD) therapy via arterial-venous (A-V) access. However, the exact timing for the development of the PHT is unknown. This study was designed to evaluate changes in pulmonary artery pressure (PAP) following creation of the vascular access. Patients and Methods: PAP and cardiac-output (CO) values were recorded in 12 pre-dialysis patients without PHT a few months after the access formation, before treatment with HD was started, and the prevalence of PHT was calculated. Clinical data was compared between patients with and without PHT. Results: The systolic PAP values were increased in “ve of the 12 pre-dialysis patients (42%) by 21±9 mm Hg to more than 35 mm Hg. Patients with and without PHT differed only in that CO was signi“cantly higher among the former. Conclusions: The development of PHT following access formation represents a failure of the pulmonary circulation to accommodate the access-mediated elevated CO. Pre-dialysis patients scheduled for access formation should be screened for the presence of sub-clinical PHT. “Positive” patients should proceed to peritoneal dialysis or advance to kidney transplantation; rather than getting access and HD therapy.

Health and health care in Israel: an introduction

Starting well before Independence in 1948, and over the ensuing six decades, Israel has built a robust, relatively efficient public system of health care, resulting in good health statistics throughout the life course. Because of the initiative of people living under the British Mandate for Palestine (1922-48), the development of many of todays health services predated the states establishment by several decades. An extensive array of high-quality services and technologies is available to all residents, largely free at point of service, via the promulgation of the 1994 National Health Insurance Law. In addition to a strong medical academic culture, well equipped (albeit crowded) hospitals, and a robust primary-care infrastructure, the country has also developed some model national projects such as a programme for community quality indicators, an annual update of the national basket of services, and a strong system of research and education. Challenges include increasing privatisation of what was once largely a public system, and the underfunding in various sectors resulting in, among other challenges, relatively few acute hospital beds. Despite substantial organisational and financial investment, disparities persist based on ethnic origin or religion, other socioeconomic factors, and, regardless of the countrys small size, a geographic maldistribution of resources. The Ministry of Health continues to be involved in the ownership and administration of many general hospitals and the direct payment for some health services (eg, geriatric institutional care), activities that distract it from its main task of planning for and supervising the whole health structure. Although the health-care system itself is very well integrated in relation to the countrys two main ethnic groups (Israeli Arabs and Israeli Jews), we think that health in its widest sense might help provide a bridge to peace and reconciliation between the country and its neighbours.

Acute renal infarction from a cardiac thrombus

Background A 53-year-old man presented to hospital 2 hours after the abrupt onset of left upper abdominal pain. He was treated with analgesics and discharged after 4 hours of observation, but presented to another hospital 2 hours later with severe left abdominal pain. His past medical history included ischemic dilated cardiomyopathy due to recurrent myocardial infarction.Investigations Physical examination, electrocardiography, laboratory investigations, contrast-enhanced computed tomography, and transesophageal echocardiography.Diagnosis Renal artery thromboembolism resulting from dilated cardiomyopathy, severely reduced cardiac function and an intracardiac thrombus.Management Anticoagulation with unfractionated heparin followed by enoxaparin and warfarin.

Characterization of Pulmonary Venous Hypertension Patients with Reactive Pulmonary Hypertension as Compared to Proportional Pulmonary Hypertension

Background: Patients with pulmonary venous hypertension (PVH) secondary to left heart disease can be further classified according to their hemodynamic profile: pulmonary hypertension (PH) in proportion to the pulmonary capillary wedge pressure (PCWP) and PH out of proportion to the PCWP or reactive PH. Currently, there are no measures that enable prediction of the development of reactive PH in patients with left heart disease. Objectives: In this study, we aim to characterize PVH patients with reactive PH as compared to proportional PH in an attempt to create a distinct profile for patients with left heart disease carrying a high risk for the development of reactive PH. Methods: Thirty-three PVH patients with reactive PH and 29 PVH patients with proportional PH were analyzed retrospectively over a 6-year period. Clinical, laboratory, echocardiographic and hemodynamic parameters were noted and compared between subgroups. Results: There was no significant difference between PVH patients with reactive and proportional PH with regard to gender, age (65.91 ± 11.9 vs. 66.69 ± 10.5 years) and body surface area (1.89 ± 0.24 vs. 1.9 ± 0.23 m2). Prevalence of the metabolic syndrome components was similar in both groups. Interestingly, PCWP was similar in both groups, as were the structural and functional parameters of the left heart. Conclusions: PVH patients with reactive PH have a similar profile as patients with proportional PH; consequently, the evolution of reactive PH is unpredictable. Therefore, it is imperative that physicians maintain a high index of suspicion for the development of reactive PH even in the early stage of heart disease.

Dilated cardiomyopathy: an unusual complication of clozapine therapy

Background A 42-year-old obese man presented with acute pulmonary edema. He had a history of chronic residual schizophrenia for which he had been taking clozapine for 7 years, but had no known prior cardiac disease. Echocardiography demonstrated severe biventricular systolic and diastolic dysfunction with severe left ventricular enlargement. Cardiac catheterization showed no coronary artery disease.Investigations Physical examination, chest radiography, electrocardiography, transthoracic echocardiography, laboratory testing, viral serology, cardiac catheterization, coronary angiography and abdominal and renal ultrasonography.Diagnosis Clozapine-induced dilated cardiomyopathy.Management Intravenous nesiritide, furosemide and morphine followed by oral heart-failure therapy comprising ramipril, metoprolol succinate, spironolactone, and furosemide. Clozapine therapy was withdrawn.

Discordance Between Hemoconcentration and Clinical Assessment of Decongestion in Acute Heart Failure

INTRODUCTIONnHemoconcentration has been proposed as a surrogate for successful decongestion in acute heart failure (AHF). The aim of the present study was to evaluate the relationship between hemoconcentration and clinical measures of congestion.nnnMETHODS AND RESULTSnWe studied 704 patients with AHF and volume overload. A composite congestion score was calculated at admission and discharge, with a score >1 denoting persistent congestion. Hemoconcentration was defined as any increase in hematocrit and hemoglobin levels between baseline and discharge. Of 276 patient with hemoconcentration, 66 (23.9%) had persistent congestion. Conversely, of 428 patients without hemoconcentration, 304 (71.0%) had no clinical evidence of congestion. Mean hematocrit changes were similar with and without persistent congestion (0.18u2009±u20093.4% and -0.19u2009±u20093.6%, respectively; Pu2009=u2009.17). There was no correlation between the decline in congestion score and the change in hematocrit (Pu2009=u2009.93). Hemoconcentration predicted lower mortality (hazard ratio 0.70, 95% confidence interval 0.54-0.90; Pu2009=u2009.006). Persistent congestion was associated with increased mortality independent of hemoconcentration (Ptrendu2009=u2009.0003 for increasing levels of congestion score).nnnCONCLUSIONSnHemoconcentration is weakly related to congestion as assessed clinically. Persistent congestion at discharge is associated with increased mortality regardless of hemoconcentration. Hemoconcentration is associated with better outcome but cannot substitute for clinically derived estimates of congestion to determine whether decongestion has been achieved.

The Human Microbiota: The Rise of an “Empire”

The human body hosts rich and diverse microbial communities. Our microbiota affects the normal human physiology, and compositional changes might alter host homeostasis and, therefore, disease risk. The microbial community structure may sometimes occupy discrete configurations and under certain circumstances vary continuously. The ability to characterize accurately the ecology of human-associated microbial communities became possible by advances in deep sequencing and bioinformatics analyses.

Vasopressin-2 Receptor Antagonist Attenuates the Ability of the Lungs to Clear Edema in an Experimental Model

In the last two decades, the role of the alveolar active sodium transport was extensively studied and was found to play a crucial role in regulating alveolar fluid clearance (AFC), and thus in keeping the airspaces free of edema. The recent development of highly selective nonpeptide vasopressin-receptor antagonists gives us a rare chance to explore the role of vasopressin in the pathogenesis of lung edema. Therefore, the present study examined the involvement of vasopressin in modulating the ability of the lung to clear edema. Vasopressin enhanced the rate of lung edema clearance by 30% as compared with untreated control rats (from 0.49 ± 0.02 to 0.64 ± 0.02 ml/h), whereas V(2) receptor antagonists significantly decreased the ability of the lung to clear water (from 0.64 ± 0.02 to 0.31 ± 0.06 ml/h; P < 0.0001). In contrast, V(1) receptor antagonist did not change the rate of AFC. The administration of ouabain (a Na,K-ATPase inhibitor) and amiloride (a Na(+) channel blocker) inhibited the stimulatory effects of vasopressin (from 0.64 ± 0.02 to 0.22 ± 0.02 ml/h [P < 0.0001] and from 0.64 ± 0.017 to 0.23 ± 0.02 ml/h [P < 0.0001], respectively). Vasopressin significantly increased Na,K-ATPase protein abundance in the basolateral membranes of the alveolar epithelial cells via V(2) receptor activation. We report a novel role of the vasopressin pathway in AFC. This observation indicates a beneficial role of vasopressin in AFC by up-regulating active sodium transport.

Acute obstructive jaundice and chronic cirrhosis protect against the adverse renal effects of pneumoperitoneum: role of nitric oxide.

BackgroundObstructive jaundice and cirrhosis are associated with impaired renal function. Previously we demonstrated that increased intra-abdominal pressure (IAP, pneumoperitoneum) in normal rats induced renal dysfunction. This study investigated the renal effects of pneumoperitoneum in rats with acute jaundice and cirrhotic rats.MethodsFollowing a baseline period, rats with obstructive jaundice or cirrhosis induced by acute or chronic bile duct ligation (BDL), respectively, and their sham-controls were subjected to consecutive IAPs of 10 and 14xa0mmHg for 45xa0min each. Urine flow (V), Na+ excretion (UNaV), glomerular filtration rate (GFR), renal plasma flow (RPF), and urinary NO metabolites (