The safety of dipyridamole in patients undergoing myocardial perfusion scintigraphy prior to lung volume reduction surgery

Patients with end-stage chronic obstructive pulmonary disease (COPD) underg oing lung volume reduction surgery (LVRS) are at high risk of peri-operativ e cardiac complications, and myocardial perfusion scintigraphy (MPS) is com monly used for risk stratification. This study prospectively assessed the s afety of dipyridamole in these patients and compared the incidence of side- effects (particularly dyspnoea) with that in patients undergoing dipyridamo le MPS prior to elective non-cardiothoracic surgery. Fifty patients were en rolled: 25 in the LVRS cohort (13 males, 12 females), with a mean age of 65 years and a mean FEV1 of 0.791, and 25 (with no history of asthma or COPD) in the control cohort (14 males, I I females), with a mean age of 66 years . Fourteen patients (56%) in each group developed side-effects. Dyspnoea wa s reported by five patients (20%) in the LVRS and two patients (8%) in the control cohort (P=NS). One patient in each cohort developed severe hypotens ion and bradycardia. Eight (32%) other patients developed minor side-effect s in the LVRS cohort compared with 11 (44%) in the control group. All side- effects responded promptly to intravenous aminophylline. In summary, there was a statistically non-significant increase in the incidence of dyspnoea i n patients with end-stage COPD and all side-effects responded to aminophyll ine. Thus, dipyridamole can be used safely in these patients.