Jorge Jalil M

Selective training of respiratory muscles in patients with chronic heart failure

Background: Patients with chronic heart failure have a lower inspiratory muscle strength and fatigue endurance. Aim: To assess the effects of selective training of respiratory muscles in patients with heart failure. Patients and methods: Twenty patients with stable chronic heart failure, aged 58.3 ± 3 years with an ejection fraction of 28 ± 9%, were subjected to respiratory muscle training with threshold valves. The load was fixed in 30% of maximal inspiratory pressure (PImax) in 11 and in 10% of PImax in nine. Two sessions of 15 minutes, 6 days per week, during 6 weeks were done. Degree of dyspnea (Mahler score), maximal oxygen uptake, distance walked in 6 minutes, respiratory muscle function and left ventricular ejection fraction were measured before and after training. Results: Both training loads were associated to an improvement in dyspnea (+2.7 ± 1.8 and +2.8 ± 1.8 score points with 30% Plmax and 10% PImax respectively), maximal oxygen uptake (from 19 ± 3 to 21.6 ± 5 and from 16 ± 5 to 18.6 ± 7 ml/kg/min with 30% PImax and 10% PImax respectively, p< 0.05), PImax (from 78 ± 22 to 99 ± 22 and from 72 ± 34 to 82.3 cm H20 with 30% Plmax and 10% PImax respectively), sustained PImax (from 63 ± 18 to 90 ± 22 and from 58 ± 3 to 69 ± 3 cm H20 with 30% PImax and 10% PImax respectively), and maximal sustained load (from 120 ± 67 to 195 ± 47 and from 139 ± 120 to 192 ± 154 g with 30% PImax and 10% PImax respectively). The distance walked in 6 min only increased in subjects trained at 30% PImax (from 451 ± 78 to 486 ± 68 m). Conclusions: Selective training of respiratory muscles results in a functional improvement of patients with chronic heart failure. (Rev Med Chile 2001; 129: 133-39).

Recomendaciones sobre el uso de la monitorización ambulatoria de presión arterial.: Documento de consenso de la Sociedad Chilena de Hipertensión

Continuous ambulatory blood pressure monitoring is a diagnostic technique devised as a consequence of the great variations in blood pressure measurements. It allows multiple daily measurements, nocturnal monitoring, avoids the stress of blood pressure measurements, gives a picture of pressure behavior during 24 hours and reduces observer related errors. The equipment used must be accurate and validated using international protocols. Accepted indications for continuous ambulatory blood pressure monitoring are white coat hypertension, episodic hypertension, resistance to medications and assessment of symptoms or autonomic dysfunction. Other indications with less clear cut usefulness, are high risk cardiac, renal or pregnant patients and an accurate blood pressure control. We describe equipment calibration, elements that must be considered in the reports, result interpretation and conclusions. Normal blood pressure ranges for children and pregnant women are also reported.

Experiencia de 36 años con marcapasos implantables: Un análisis histórico

Background: The implantation of pacemakers improves cardiac function and quality of life, in particular with dual chamber DDD and DDDR modes. Aim: To evaluate our clinical experience and results on pacemaker implantation, from 1963 to 1998. Material and methods: Computerized data collected from 2,445 consecutive paced patients was reviewed. A total of 3,554 operative procedures were performed, including 412 procedures for complications and 697 pacemaker replacement. Patient survival was determined from clinical records, inquiry to pacemaker manufacturers and death certificates from Servicio de Registro Civil e Identificacion de Chile (Chilean Civil and Identification Registry). Results: Use of dual chamber (DDD and DDDR) pacemakers increased progressively up to 74% from 1988 to 1998. Complication rate was 42% in the 1963-1976 study period, it decreased to 10.6% in the 1977-1987 study period, and to 5.6% by 1988-1998. Only two patients died during surgery in the study period (0.08%). In the 1977-1987 period, pacemakers lasted 10.6 years. Survival rates were 52% at ten years, 33% at 15 years, and 21% at 20 years, with a median survival of 11.7 years, and 7.24 years in patients over 80 years old. Conclusions: Transvenous permanent pacing can be accomplished today with a low complication rate, mainly due to better technology and surgical procedures (Rev Med Chile 2002; 130: 132-42)

Desensibilización rápida en pacientes con hipersensibilidad a aspirina sometidos a angioplastía coronaria: Reporte de cuatro casos

Aspirin use is necessary after a coronary angioplasty. It should not be used in patients with a history of hypersensitivity. However, rapid desensitization protocols have been reported to allow its use in such patients. One of these protocols consists in the administration of progressive doses of aspirin, from 1 to 100 mg in a period of 5.5 hours, in a controlled environment. We report four male patients aged 45,49, 59 and 73 years with a history of aspirin hypersensitivity, who were subjected to a coronary angioplasty. In all, the rapid aspirin desensitization protocol was successfully applied, allowing the use of the drug after the intervention without problems.

La hiperuricemia es un marcador del umbral anaeróbico en la insuficiencia cardíaca crónica

Background: Patients with chronic cardiac failure often have elevated plasma uric acid levels, that are associated to a dismal prognosis. Aim: To investigate possible metabolic mechanisms to explain elevated uric acid levels in these patients. Patients and methods: Eighteen patients with chronic cardiac failure aged 61 ± 10 years old, without gout or renal failure and not using high doses of diuretics (equal or less than 80 mg/day furosemide or 50 mg/day hydrochlorothiazide) were studied. Plasma uric acid levels were correlated with anaerobic threshold, maximal oxygen uptake, plasma noradrenaline and creatinine and left ventricular ejection fraction, measured radioisotopically. Results: Mean maximal oxygen uptake was 16.6 ± 4.2 ml/kg/min. There was a negative correlation between uric acid levels and maximal oxygen uptake or maximal oxygen uptake/body surface area (r=0.521 and -0.533 respectively, p<0.05). Patients with uric acid levels over 7 mg/dl had a lower anaerobic threshold than patients with lower levels (9.81 ± 2.41 and 13.08 ± 3.28 ml/kg/min respectively, p<0.05). No significant differences in maximal oxygen uptake were observed in these two groups of patients (15.5 ± 4.24 and 18.08 ± 3.86 ml/kg/min respectively). Uric acid levels did not correlate with plasma noradrenaline, creatinine or lefi ventricular ejection fraction. Conclusions: These results suggest that a defect in cellular oxygenation contributes to the elevation of plasma uric acid levels in patients with chronic cardiac failure. (Rev Med Chile 2001; 129: 503-8)

Utilidad de isosorbide sublingual en la reversibilidad de la hipertensión pulmonar reactiva, en pacientes candidatos a trasplante cardíaco

Prospective evaluation of patients referred forcardiac transplant evaluation. Patients underwent right catheterization for hemodynamicmeasurements at baseline and after repeated doses of 5 mg sublingual isosorbide every 5 minutes untilobserving a decrease in pulmonary vascular resistance decrease or symptomatic hypotension.