Adenosine myocardial SPECT--its efficacy and safety and correlation with coronary angiogram.

OBJECTIVE: The aim of this study was to determine the safety and efficacy of adenosine Tc99m sestamibi myocardial perfusion study under controlled conditions and to correlate the adenosine Tc99m sestamibi perfusion defects and the coronary angiography in patients investigated for coronary artery disease. METHODS: This prospective study included 122 consecutive patients who underwent adenosine Tc99m sestamibi single photon emission computed tomography (SPECT) myocardial perfusion study. Seventy two patients had coronary angiographic correlation. All the patients who were referred by the cardiologists for stress myocardial perfusion scan who could not be stressed physiologically for one reason or the other were included in the study. RESULTS: Among the coronary angiography group the overall sensitivity, specificity, positive predictive value and negative predictive value of adenosine Tc99m sestamibi single photon emission computed tomography myocardial perfusion study for detecting significant coronary obstruction (diameter > or = 50%) were 94.4%, 79%, 85% and 92% respectively. The side effects were transient and required no treatment. CONCLUSION: We conclude adenosine Tc99m sestamibi single photon emission computed tomogram myocardial perfusion study is a reliable test with high sensitivity and specificity for the detection of coronary artery disease.

Adenosine-induced chest pain: is it due to myocardial ischaemia? Clinical, electrocardiographic, haemodynamic and metabolic study.

Adenosine has recently been demonstrated to be a mediator of angina in human beings. The present study was undertaken to document the presence or absence of myocardial ischaemia on clinical, haemodynamic, electrocardiographic and metabolic evidences after intracoronary administration of adenosine. Fifteen patients with chronic stable angina (12 males and 3 females), positive exercise stress test and documented significant stenosis of the left anterior descending coronary artery (LAD) were included in the study. The surface and intracoronary electrocardiograms (ECGs), pulmonary artery diastolic pressure and coronary sinus lactate levels were monitored at baseline and after intracoronary administration of adenosine in all patients. Adenosine was administered intracoronary in doses of 1000-8000 microgram depending on the provocation of chest pain. Typical angina was observed in all patients. There were no signs of ischaemia on surface or intracoronary ECG. There was no statistically significant difference between the pulmonary artery diastolic pressure and coronary sins lactate levels at baseline and post-adenosine administration (p > 0.05). It is concluded that intracoronary administration of adenosine produces chest pain in patients with chronic stable angina by mechanism other than myocardial ischaemia.