Alejandro Martínez S

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).

Enfermedad periodontal en pacientes con síndrome coronario agudo

BACKGROUND Epidemiological studies suggest an association between periodontal disease and coronary heart disease. It is possible that periodontal disease may contribute to plaque destabilization in patients with acute coronary syndrome. AIM To assess the association between severity of periodontal disease, the number of acute plaques and extension of coronary artery disease in patients with acute coronary syndrome. PATIENTS AND METHODS The severity of periodontal disease was assessed by skilled independent observers in patients with acute coronary syndrome subjected to coronary angiography. The periodental disease was classified as mild or severe. Acute plaques were defined on angiography as those with thrombi, ulcers or flow alterations. The extension of coronary disease was analyzed using the Sullivan score. RESULTS Forty three patients (35 males) aged 41 to 83 years, were studied. Mild and severe periodontal disease was present in 18 (42%) and 25 (58%) patients respectively. Seventy six percent of those with severe disease had two or more acute plaques, compared with 17% of those with mild disease (p<0.001). Median Sullivan score was 80.6 and 57.2 in patients with severe or mild periodontal disease respectively (p=0.001). CONCLUSIONS Severe periodontal disease was associated with a higher number of acute coronary plasques and a higher extension of coronary artery disease, in patients with acute coronary syndromes.

Potencia de los músculos inspiratorios en insuficiencia cardíaca crónica y en enfermedad pulmonar obstructiva crónica

BACKGROUND: The maximal pressure generated by inspiratory muscles (PIMax) is an index of their strength which is diminished in both chronic obstructive pulmonary disease (COPD) and chronic heart failure (CHF). Although inspiratory muscle power output (IMPO), which includes both strength and velocity of shortening, has been shown to be reduced in COPD, there is no information regarding IMPO in CHF. AIM: To measure IMPO in patients with CHF and COPD. PATIENTS AND METHODS: We studied 9 CHF patients with functional capacity II and III and 9 patients with severe COPD. Eight normal subjects of similar ages were included as controls. Power output was measured using the incremental threshold loading test. RESULTS: Maximal IMPO was significantly reduced in both groups of patients. Power output developed with each increasing load was also diminished, basically as a consequence of a reduction in Vinsp. The degree of dyspnea at the end of the test was greater in COPD than in CHF patients and normal subjects. For a given level of power, dyspnea was also greater in patients than in normals subjects. There was no decrease in SpO2 during the test. CONCLUSIONS: IMPO is equally reduced in COPD and CHF patients. Power output is better related to dyspnea than PIMax, probably because of the inclusion of shortening velocity.

Tratamiento de la insuficiencia cardíaca avanzada mediante trasplante de corazón

Background: Heart transplantation currently provides the most effective treatment for advanced heart failure. However, medical therapy for this condition has also improved, heart donors are scarce and the cost of the procedure is high. Therefore the indications and management of these patients need reevaluation. Aim: To analyze the results of 24 patients submitted to heart transplantation for end-stage heart failure needing repeated hospitalizations and i.v. inotropes for compensation. Patients and methods: The group was comprised by 21 men and 3 women with a mean age of 36.8 years, mean left ventricular ejection fraction 19±4.5%, mean systolic pulmonary artery pressure 48±13 mmHg (24-70) and mean pulmonary vascular resistance 2.6 Wood Units (1-5). Fourteen patients (58%) had a previous median sternotomy. Immunosupression did not include induction therapy and steroids were discontinued early. Results: Operative mortality was 4% at 30 days. Actuarial survival at one year was 90% and at 5 years 72%. Freedom from rejection at one year was 76% and at 5 years 50%. Freedom from infection was 70% at one year and 56.5% at five years. All patients with more than 3 months of follow-up were in functional class I. Conclusions: These results justify the proposed modifications for transplantation protocols (Rev Med Chile 2001; 129: 9-17).

Mortalidad post infarto del miocardio en Chile: Comparación de los registros de angioplastía primaria versus trombolisis

ResumenAntecedentes: Desde el ano 2005, se ha implementado en nuestro pais un conjunto de politicas publicas para permitir un acceso universal al tratamiento trombolitico a los pacientes con infarto agudo del miocardio (IAM). Para evaluar sus resultados es importante establecer los estandares locales de las distintas opciones de reperfusion. Objetivos: 1) Comparar la mortalidad precoz y alejada de los pacientes con IAM sometidos a angioplastia primaria (angioplastia) versus los sometidos a trombolisis, en Chile. 2) Establecer los factores de riesgo de mortalidad en estos pacientes. Metodos: Utilizando los registros nacionales de angioplastia (RENAC) y de IAM (GEMI), seleccionamos a todos los pacientes con IAM tratados con angioplastia o trombolisis, durante los anos 2003 y 2004. Entre ellos, comparamos mediante prueba de t de Student o chi-cuadrado, segun correspondiera, sus caracteristicas basales y su mortalidad hospitalaria, a 30 dias, y a 12 y 24 meses. Ademas se hizo analisis de regresion logistica multivariado para identificar

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.

Tratamiento crónico combinado con iloprost y sildenafil en un paciente con hipertensión pulmonar primaria

Iloprost, a prostacyclin analogue administered by inhalation,improves hemodynamic and functional class variables in patients with primary pulmonaryhypertension. However, repetitive inhalations are required due to its short term effects. Onepotential approach to prolong and increase the effects of aerosolized iloprost might be tocombine its use with phosphodiesterase inhibitors. We report a 36 years old female patient withprimary pulmonary hypertension treated with this combination. After 18 months of therapy thepatient had an improvement in functional class and in the 6 min walk distance despitepersistence of high pulmonary pressures. Our case is in agreement with the reported beneficialeffect of the association of sildenafil and iloprost. We postulate that functional improvement inprimary pulmonary hypertension is not always related to a decrease in pulmonary arterypressure (Rev Med Chile 2004; 132: 353-6).(

Valor pronóstico de la hiperuricemia en la insuficiencia cardíaca crónica

Background: Hyperuricemia has been proposed as a risk marker in chronic heart failure, but its value as an independent prognostic is not well established. Aim: To determine the prognostic value of hyperuricemia, in patients with chronic stable heart failure. Patients and methods: Forty six male patients with chronic heart failure, aged 62±13 years, were studied. Their ejection fraction was less than 40% and their serum creatinine was less than 2 mg/dl. Serum uric acid and catecholamines, maximal oxygen consumption (VO 2 max) and left ventricular ejection fraction were measured. Mortality and the need for cardiac transplant were recorded as endpoints during a mean follow up of 39±18 months. The relationship between basal measures and the occurrence of events was analyzed using univariate and multivariate methods. Results: Basal VO 2 max and left ventricular ejection fraction were 16±4.6 ml/kg/min and 22±7% respectively. Eighteen patients died and three required transplantation during the follow up. Patients reaching these endpoints had a lower VO 2 max and left ventricular ejection fraction and higher uric acid levels. Multivariate analysis accepted left ventricular ejection fraction (relative risk 0.89, 95% CI 0.82-0.97) and serum uric acid (relative risk 1.335 95% CI 1.02-1.74) as significant predictors of events. The relative risk for cardiac transplantation was 7.07 times higher among those with a serum uric acid over 7 mg/dl. Conclusions: A high serum uric acid is an independent predictor of bad prognosis in patients with stable chronic heart failure (Rev Med Chile 2004; 132: 1031-6). (Key Words: Heart failure, congestive; Hyperuricemia; Stroke volume; Ventricular ejection fraction)

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)

Resultados a largo plazo de la valvuloplastía mitral con balón

BACKGROUND Mitral balloon valvuloplasty (MBV) is the therapy of choice for the treatment of symptomatic mitral stenosis with suitable anatomy. Although its short and mid-term results are favorable, there is a paucity of information about long-term follow-up. AIM To assess the late results of MBV. MATERIAL AND METHODS A cohort of 225 patients aged 8 to 20 years who were subjected to a MBV from 1989 to 2001, was studied. All variables at the time of the procedure, short and long-term results and major events during follow-up (new mitral intervention and mortality) were recorded. Uni and multivariate analysis were used to assess prognosis. RESULTS The mean follow-up lapse was 13.5 years (range 8 to 20 years). During this period, 88 patients (39.1%) remained event-free and in acceptable functional capacity. Eight percent died, 8% required a second MBV and 43.5% required a surgical mitral valve replacement. A post-procedural area equal or greater to 1.9 cm² was associated with a greater likelihood of free-event survival (log rank test: p = 0.02/Cox proportional regression model: coefficient 0.54, p = 0.04). CONCLUSIONS MBV is effective, although there is a high chance of new interventions in the long-term follow-up. A larger post-procedure mitral area is associated with a better prognosis.