Ischaemia during exercise and ambulatory monitoring in patients with stable angina pectoris and healthy controls. Gender differences and relationships to catecholamines

AIMS: To evaluate signs of ischaemia and ventricular arrhythmias in relation to gender and sympathoadrenal activity in patients with stable angina pectoris and healthy controls. MATERIAL AND METHODS: 809 patients (248 females) with stable angina pectoris, and 50 matched healthy controls performed an exercise test and an ambulatory ECG recording. Catecholamines were measured in plasma before and immediately after exercise, and in urine during ambulatory ECG. RESULTS: Male and female patients showed similar frequencies of ST-depression, similar blood pressure and catecholamine responses on exercise testing. Females had higher heart rates and were more prone towards silent ischaemia. The healthy controls exercised longer and showed greater adrenaline responses. During ambulatory ECG, the two genders had similar duration of ST-depression, but males had more premature ventricular complexes. Females excreted more noradrenaline, and had higher minimal and maximal heart rates. Premature ventricular complexes were equally common among patients and controls, but controls had greater catecholamine excretion. Maximal ST-depression during exercise was positively related to the duration of ST-depression during ambulatory ECG for both genders. Exercise time until ST-depression was inversely related to the duration of ST-depression during ambulatory ECG among male patients only. Catecholamine responses during exercise testing were more closely correlated to time until chest pain than to signs of ischaemia. CONCLUSION: Mechanisms behind myocardial ischaemia and arrhythmias may differ in male and female patients, as females seem to be more prone towards silent ischaemia. Ischaemia on exercise correlated to ambulatory ischaemia among males only.