Muhammad Shah Gilani.
Coronary heart disease; predictive value changes in R-wave amplitude after exercise.
Professional Med J Jan ;15(2):255-9.

To assess the value of coronary events reflected by changes in R-wave amplitude after exercise. Setting: Nishtar Hospital, Sultan. Duration. One year. Study Design: comparative study. Material and Methods: Sample size 146 patients. Sampling Technique: Convenient probability sampling done. Results: All patients were followed up for 6 months, during which time myocardial infarction and death of cardiovascular origin were considered endpoints. The incidence of events in patients in whom R-wave amplitude decreased (normal response) and in those in whom R-wave amplitude did not change or increase (abnormal response) was compared. The incidence of coronary events in patients with a normal response was 23% and in those with an abnormal response, 45.8% (p<0.01). Correlating the results with several non invasive and angiographic variables, an abnormal R-wave response showed a significantly higher rate of events in the subsets of patients with prior myocardial infarction, absence of cardiomegaly, maximal functional capacity lower than 4 SETs, maximal heart rate higher than 140 beats/min and abnormal left ventricular function. Conclusion: The changes in R-wave amplitude after exercise is a variable that should be taken into account when assessing the risk of future events in patients with coronary heart disease.

PakMediNet -Pakistan's largest Database of Pakistani Medical Journals - http://www.pakmedinet.com