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J Navia

Publications and source records attributed to J Navia.

At least 37 records · Page 2Linked to original sources
PubMed1996

Does successful bridging with the implantable left ventricular assist device affect cardiac transplantation outcome?

OBJECTIVES: We sought to determine whether cardiac transplant recipients who required a bridge to transplantation with an implantable left ventricular assist device had a different outcome than patients who underwent transplantation without such a bridge. METHODS: A retrospective study of 256 cardiac transplants from 1992 to 1996 included 53 patients who received the HeartMate left ventricular assist device and 203 patients who had no left ventricular assist device support. RESULTS: Left ventricular assist device transplants increased from 8% of all transplants in 1992 (n = 63) to 32% in 1995 (n = 65) and 43% in 1996 (n = 14 year to date). Patients with and without left ventricular assist device had similar age and sex distributions. Left ventricular assist device recipients were larger (body surface area 1.96 vs 1.86 m2, p = 0.004). They were more likely to have ischemic cardiomyopathy (70% vs 45%, p = 0.001) and type O blood group (51% vs 34%, p = 0.06). All patients with left ventricular assist device and 42% of those without had undergone previous cardiac operations by the time of transplantation (mean number per patient 1.5 vs 0.3, p < 0.001). More patients in the left ventricular assist device group had anti-HLA antibodies before transplantation (T-cell panel reactive antibody level > 10% in 66% of left ventricular assist device group vs 15% of control group, p < 0.0001). Waiting time was longer for the left ventricular assist device than for patients in status I without a left ventricular assist device (median 88 vs 37 days, p = 0.002). There was no difference in length of posttransplantation hospital stay (median 15 days for each) or operative mortality (3.8% vs 4.4%). Mean follow-up averaged 22 months. No significant difference was found in Kaplan-Meier survival estimates. One-year survival was 94% in the left ventricular assist device group and 88% in the control group (difference not significant). Comparison of posttransplantation events showed no significant difference in actuarial rates of cytomegalovirus infection (20% vs 17%) or vascular rejection (15% vs 12%) at 1 year of follow-up. Similar percentages of patients were free from cellular rejection at 1 year of follow-up (12% vs 22%, p = 0.36). CONCLUSIONS: Left ventricular assist device support intensified the donor shortage by including recipients who otherwise would not have survived to transplantation. Bridging affected transplant demographics, favoring patients who are larger, have ischemic cardiomyopathy, have had multiple blood transfusions and complex cardiac operations, and are HLA sensitized. Successfully bridged patients wait longer for a transplant than do UNOS status I patients without such a bridge, but they have similar posttransplantation hospital stay, operative mortality, and survival to those of patients not requiring left ventricular assist device support.

Adult↗
PubMed1987

Treatment of descending thoracic aneurysm with an intraaortic occluder.

Elective treatment of descending thoracic aneurysms involves direct surgery, with Dacron graft replacement of the diseased aortic segment. When the patient's condition contraindicates major surgery, however, the surgeon should consider using an extraanatomic approach-implanting an ascending aorta-to-abdominal aorta Dacron bypass graft in a ventral position and leaving the diseased segment undisturbed. After such a procedure, the descending thoracic aorta must be excluded from the normal circulation. For this purpose, we have designed an intraaortic occluding technique in which an umbrella-like device is implanted immediately distal to the left subclavian artery. This technique has proved safe and uncomplicated in canine experiments and is ready for clinical trials.

Journal Article↗
PubMedDate not supplied

High lead exposures resulting from pottery production in a village in Michoacán State, Mexico.

This paper reports findings from a screening study conducted to examine potential lead (Pb) exposures in residents of a Mexican village where Pb oxide continues to be used in ceramic pottery production. Extremely high Pb concentrations were measured in personal and indoor air samples, household surface dust samples, and household soil samples. Personal air Pb concentrations for workers performing pottery firing and glazing were up to 454 microg/m3. Results from indoor air samples indicate that airborne Pb concentrations were lower during nonglazing period compared to the glazing period. Soil Pb concentrations measured in 17 homes ranged from 0.39 to 19.8 mg/g. Dust Pb loading on surfaces of household items, hands, and clothes of a worker ranged from 172 to 33,060 microg/ft2. Pb content as high as 2.4 microg/g was found in a bean stew cooked in a pot made in the village. Based on these Pb concentrations measured in multiple media and data adapted for exposure contact rates, we have made rough estimates of Pb exposures via inhalation, soil/dust ingestion, and food ingestion. Estimated total daily Pb intake, on average, is 4.0 mg for adults and 3.4 mg for children living in the village. In the total daily intake, a greatest fraction may be contributed by food ingestion and another significant fraction may come from soil/dust ingestion for the children. Although the sample size is small, these measurements indicate a very significant public health problem for the village residents and a large number of other similar communities in Mexico. (It was estimated that there are approximately 1.5 million glaze potters.) The Pb exposure is implicated in a number of pervasive health problems in the region, and is the cause for national and international attention. Several recommended solutions to this problem range from personal protection and behavioral changes to introduction of alternative glazes.

Adult↗
PubMedDate not supplied

Pulmonary hypertension is not a risk factor for RVAD use and death after left ventricular assist system support.

Unlike transplantation candidates, patients with pulmonary hypertension (PHTN) and a high transpulmonary gradient do not appear to be at increased risk for right ventricular dysfunction after left ventricular assist system implant. To verify this observation, we reviewed 63 patients supported with the HeartMate (Thermo Cardiosystems, Inc, Woburn, MA) left ventricular assist system. Patients were divided into two groups: patients with PHTN (47 patients) had mean pulmonary artery pressure > 30 mm Hg and/or pulmonary vascular resistance > 4 Wood units, and the remainder of patients did not have PHTN (16 patients). Both groups were similar in age (mean, 51 years), gender distribution (% men, 83% vs 94%, not significant), and number of patients with ischemic cardiomyopathy (72% vs 69%, not significant). More patients in the group without PHTN required extracorporeal membrane oxygenation support (38% vs 12%, p = .06). Right ventricular assist device support was instituted in five (11%) patients with PHTN and four (25%) patients without PHTN. A significantly larger number of patients without PHTN died while on support (14% vs 44%, p = .01). Survival after transplantation in both groups was > 90%. Patients with PHTN have higher transpulmonary gradient, show a significant decrease in pulmonary pressure after left ventricular assist system implantation, and have a higher transplantation rate compared to patients without PHTN. A larger patient cohort is needed to determine if the absence of PHTN is a risk factor for RVAD need and poor outcome after LVAS support.

Cardiomyopathies↗
PubMedDate not supplied

[Anesthesia for cesarean section in a patient with von Hippel-Lindau disease].

We report the case of a pregnant 38-year-old woman at full-term who had a history of von Hippel-Lindau disease with neurological symptoms. She had previously undergone surgical removal of cerebellar hemangioblastomas. A cesarean delivery performed under general anesthesia was uneventful and the outcomes were excellent for both mother and fetus. General anesthesia was chosen because patients with von Hippel-Lindau disease often have asymptomatic spinal cord and intracranial involvement. As such involvement could not be ruled out, we preferred to avoid the risks related to regional anesthesia. One of the main features of von Hippel-Lindau disease is the presence of central nervous system hemangioblastomas, which are highly vascularized, slow growing tumors that may become enlarged during pregnancy. We describe the implications of the disease for anesthesia.

Adult↗
PubMedDate not supplied

[Myocardial revascularization: isoflurane and halothane. Our experience].

The use of isofluorane in coronary patients has been questioned due to the coronary steal syndrome that this agent is said to produce with changes in the myocardial lactate extraction, ST segment changes or T wave inversion. Three hundred fifty nine patients underwent coronary revascularization were studied. The anaesthesia was carried out with halothane (146 patients) or isofluorane (213 patients) as volatile agents of a balanced anesthetic technique based on high doses of narcotics. We found no correlation between the use of isofluorane and ST changes or T wave inversion. The appearance of myocardial infarction between the 2 groups was also no statistically difference (p = 0.61).

Female↗