Encontrando sistemáticamente los test de esfuerzo negativos en pacientes con enfermedad coronaria asociada a enfermedad pulmonar obstructiva crónica asintomáti-ca, nos indujo a revisar el comportamiento hemodinámi-co en ejercicio, en estos enfermos.

Se estudiaron 15 pacientes con enfermedad pulmonar obstructiva crónica, divididos en dos grupos: Grupo I (moderados), con VEMS superior a 1600 ce, compuesto por nueve pacientes. Al ejercicio no se incrementaron las presiones y resistencias pulmonares, incrementándose ostensiblemente el gasto cardiaco. Grupo II (severos) con VEMS inferior a 1600 ce, compuesto por seis pacientes; al ejercicio se comportaron inversamente, incrementándose las presiones pulmonares y acentuándose menos el gasto cardiaco.

Este estudio nos muestra que, en pacientes con dicha enfermedad sometidos a test ergométrico para valoración coronaria, nos eleva la incidencia de falsos negativos, pues el incremento de presiones y resistencias pulmonares, puede limitar el incremento del gasto y precar-ga ventricular izquierda, impidiendo llegar a limites aeró-bicos, que provoquen la isquemia miocárdica.

Concluimos resaltando la necesidad previa de un test de función pulmonar, antes del test de ejercicio, dada la pérdida de sensibilidad del test, en presencia de enfermedad pulmonar obstructiva crónica, aún en fase asintomática.

The finding of systematically negative exercise test in patients with coronary artery disease associated to asymptomatic chronic obstructive lung disease prompted us to review the hemodynamic behaviour of these patients during exercise.

15 patients with chronic obstructive lung disease were studied. 9 patients were included in group I (moderate disease), with FEV1 greater than 1600 cc. These patients did not show a rise in pulmonary pressures and resistan-ces during exercise, and an outstanding increase in cardiac output appeared. 6 patients were included in group II (severe disease), with FEV1 lower than 1600 cc; they showed a behaviour during exercise opposed to that seen in group I, with a rise in pulmonary pressures and a lesser increase in cardiac output.

The present study shows that, in patients with chronic obstructive lung disease, exercise test for coronary artery disease evaluation has a higher prevalence of false negative results. These are the consequence of a limitation of the left ventricular output and preload caused by an increase in pulmonary pressures and resistances; therefo-re, aerobic limit leading to myocardial ischemia is not reached.

Finally, the need for a pulmonary function test previous to the performance of an exercise test is stressed in view of the lower sensitivity of the latter with chronic obstructive lung disease even in asymptomatic stage.