The feasibility and safety of graded adenosine stress test for myocardial perfusion in asthmatic and/or COPD patients.

SUBJECT AND METHODS: A total of 40 patients (M:F::26:14; age range: 37-84yrs; mean: 64.1yrs) with known chronic obstructive pulmonary disease (COPD) (ranging from mild to severe), referred for a stress myocardial perfusion study, were included in this study over a period of one year. All patients underwent adenosine stress in a titrated protocol and pre-infusion of short acting bronchodilator salbutamol 2 puffs few minutes prior to start adenosine infusion. In a fraction of 26 patients, pulmonary function tests (PFT) were performed and used in addition to clinical examination to classify the severity of pulmonary obstruction. On the basis of forced expiratory volume in one second (FEV1) on PFT, 4 patients had a mild disease (FEV1 60%-80%), 17 had a moderate obstructive disease (FEV1 41%-59%) and 4 had severe COPD/asthma (FEV1 <40%) while 2 patients had normal >95% FEV1. Post-stress questionnaire to assess subjective tolerance and symptoms were undertaken for all patients.

RESULTS: The results demonstrated an excellent tolerance to adenosine infusion in this group of patients, with adequate stress achieved in all. None had complaints of severe dyspnoea or respiratory distress requiring medical intervention. Thirteen patients had mild to moderate degree dyspnoea during infusion. The study included a significant number of 23 elderly patients (>65 years), who showed better tolerance than the younger patients.

CONCLUSION: In this pilot study in patients with COPD who referred for myocardial perfusion scintigraphy, the feasibility and safety of adenosine in a graded protocol along with a good pre-stress assessment and a short acting bronchodilator treatment was documented.