Israel Medical Association Journal

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.

Background: Data regarding the epidemiology of secondary pulmonary hypertension are scanty.

Objectives: To describe the spectrum and relative incidence of background diseases in patients with significant secondary PHT.

Methods: We identified 671 patients with systolic pulmonary artery pressure of 45 mm Hg or more from the database of the echocardiographic laboratory. Their background diseases were recorded and classified into three subgroups: cardiac, pulmonary and pulmonary vascular disease without pulmonary parenchymal disease. Age at the first echocardiographic study, gender and systolic PAP values were recorded. Data between the three subgroups were compared.

Results: The mean age of the patients was 6515 years, mean systolic PAP 6114 mm Hg and female:male ratio 1.21:1. At the time of diagnosis 85% of the patients were older than 50. PHT was secondary to cardiac disease in 579 patients (86.3%), to PVD without PPD in 54 patients (8%) and to PPD in only 38 patients (5.7%). Mean age and mean systolic PAP did not differ significantly among the three subgroups. There was a significantly higher female: male ratio in patients with PVD without PPD compared with cardiac or pulmonary diseases (1.7:1 vs. 1.2:1 and 1.7 vs. 0.8:1 respectively, P0.05).

Conclusions: The majority of patients with significant PHT are elderly with heart disease. PVD without PPD and chronic PPD are a relatively uncommon cause of significant PHT. Since the diagnosis of PHT is of clinical significance and sometimes merits different therapeutic interventions, we recommend screening by Doppler echocardiography for patients with high risk background diseases.

Background: Exposure of newborn animals to high concentrations of oxygen leads to diffuse alveolar damage similar to that seen in bronchopulmonary dysplasia in human infants. Therefore, neonatal rats are a suitable practical model of hyperoxic lung damage in human infants.

Objective: To determine the involvement of tumor necrosis factor-alpha and interleukin-6 in lung injury in neonatal rats exposed to 100% O2 concentration.

Methods: A randomized controlled study was designed in which litters of term Sprague-Dawley rat pups were assigned to experimental or control groups. The pups in the experimental group were placed in 100% O2 from birth for 9 days, while the control pups were placed in room air. Twelve to 15 pups from each group were sacrificed on day 1, 3, 6, 9 and 13 after birth for bronchoalveolar lavage collection and lung histologic study. The bronchoalveolar lavage fluid was assayed for TNFα and IL-6.

Results: Newborn rats exposed to 100% O2 for the first 9 days of life showed severe pulmonary edema and hypercellularity on days 1 and 3, which then improved to nearly complete resolution on days 6 and 9. Pulmonary TNFα was produced early on O2 exposure (day 3) and pulmonary IL-6 later (days 6 and 9).

Conclusions: Hyperoxia induces sequential production of pulmonary TNFα and IL-6, which corresponds to the severity of the pathological findings and the known inflammatory and anti-inflammatory role of these cytokines.

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TNFα= tumor necrosis factor-alpha

IL-6= interleukin-6

Background: Anomalous origin of the left coronary artery from the pulmonary artery is a rare congenital malformation that presents a diagnostic challenge to the pediatrician and pediatric cardiologist. Although surgical repair is always indicated, the optimal technique has yet to be determined.      

Objectives: To review our experience with the diagnosis of children with ALCAPA and to assess short to midterm surgical results.

Methods: Between 1992 and 1998, 13 infants and children (2 months to 15 years) were treated for ALCAPA at our medical center. Eight were diagnosed during the first year of life; all were symptomatic and had severe dysfunction of the left ventricle. The five patients diagnosed at an older age had normal myocardial function. Diagnosis was established by echocardiography alone in seven patients; six required catheterization (one infant and all older patients). Surgery was performed in 12 patients to establish dual coronary artery system: 7 underwent the Takeuchi procedure and 5 had re-implantation of the anomalous left coronary artery.

Results: One infant died shortly after diagnosis before surgical repair was attempted, and one died postoperatively. Four patients required additional surgery: three for late complications of the Takeuchi procedure and one valve replacement for mitral insufficiency. Recent evaluation revealed good global left ventricle function in all patients except for one, who is still within the recovery phase and shows gradual improvement. However, most patients who presented with severe myocardial dysfunction upon diagnosis still display abnormal features such as echo-dense papillary muscles or evidence of small akinetic segments. In this group, early repair was associated with faster myocardial recovery.

Conclusions: The diagnosis of ALCAPA remains a clinical challenge to the pediatrician and cardiologist. Diagnosis can be established echocardiographically, and early diagnosis and treatment may lead to faster myocardial recovery. The preferred surgical method appears to be re-implantation of the ALCA. The chance for good recovery of global ventricular function is high even in the sickest patients, nonetheless abnormal myocardial features can be identified even years after surgery.

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ALCAPA= anomolous origin of the left coronary artery from pulmonary artery.

Objectives: To suggest a simple outpatient technique for evaluating the response of arterial oxygen saturation to exercise for use as a marker of disease severity.

Patients and methods: Ninety-six patients with various degrees of COPD¹ were divided into three groups: mild (forced expiratory volume in 1 sec >65%), moderate (FEV1² between 50 and 65%), and severe (FEV1 <50%). Using continuous oximeter recording we measured oxygen saturation during 15 steps of climbing, and quantified  oxygen desaturation by measuring the “desaturation area”, defined as the area under the curve of oxygen saturation from the beginning of exercise through the lowest desaturarion point and until after recovery to the baseline level of oxygen percent saturation. Desaturation was correlated to spirometry, lung gas volumes, blood gas analysis, and 6 min walking distance.

Results A good correlation was found between severity of COPD and baseline SaO2³, lowest SaO2, recovery time, and desaturation area.  A negative correlation was found between desaturation area and FEV1 (r=-0.65), FEV1/forced vital capacity (r=-0.58), residual volume to total lung capacity (r=0.52), and diffusing lung capacity for carbon monoxide (r=-0.52). In stepwise multiple regression analysis only FEV1 correlated significantly to desaturation area.  A good correlation was noted between 6 min walking distance and desaturation area with the 15 steps technique (r=0.56).

Conclusions: In patients with severe COPD, arterial hypoxemia during exercise can be assessed by simple 15 steps oximetry. This method can serve both as a marker for disease severity and to determine the need for oxygen supplementation.

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COPD = chronic obstructive pulmonary disease

FEV1 = forced expiratory volume in 1 sec

SaO2 = arterial oxygen saturation

 Background:  Pulmonary alveolar proteinosis is a rare disease in which a surfactant-like phospholipid-rich protein accumulates in the lungs. The disease is amenable to effective therapy by total lung lavage.       

Objectives: To investigate the prevalence, ethnic distribution and course of PAP  in Israel.

Methods: A countrywide survey was conducted during which pulmonologists were questioned about patients with PAP. The patients were examined and their charts, radiological images, pathological slides and physiological data were reviewed.

Results: The survey yielded 15 patients (8 females) during the period 1976–98 (14 in the last decade), giving a prevalence of 3.7x10⁶ and an incidence of 0.36x10⁶/year.

Mean age of the patients was 33±13 years (range 0.5–46 years). Seven patients were North African (two were siblings), four were from Iraq and two were Arabs; there was only one Ashkenazi Jew (a child). Symptoms at the onset were dyspnea and chest pain. Spontaneous remission occurred in at least 3 patients, and 10 patients required 1–4 bronchoalveolar lavage treatments. The subjective and physiological response was favorable, but there was less consistent radiological improvement.

Conclusion: The prevalence of PAP in Israel is approximately 3.7x10⁶. Most cases occurred in Jews who had immigrated from North Africa or Iraq, and two were siblings. The prevalence among the Arab population appears to be similar. This clustering suggests the existence of a genetic predisposition. The course of the disease appears to be similar to that reported elsewhere.

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PAP = pulmonary alveolar proteinosis