Vasodilator stress agents for myocardial perfusion imaging

Abstract

In this issue of the Journal, Yao et al report on the prognostic value of adenosine triphosphate (ATP) myocardial perfusion imaging (MPI) with Technetium-99 sestamibi (Tc-99m) in a population aged 70 years and older.1 The ability to exercise in this population is expected to be rather limited. A total of 415 patients with suspected coronary artery disease (CAD) were identified and retrospectively enrolled in the study. The primary composite end point was major adverse cardiac events (MACE) and included death from a cardiac etiology, nonfatal myocardial infarction (MI), and late coronary revascularization ([60 days). Sixteen patients met exclusion criteria as they underwent early coronary revascularization B60 days after MPI. Reversible and/or fixed perfusion defects were considered abnormal and patients were followed over a mean of 3.45 ± 1.71 years. MACE occurred in 37 patients, including 9 cardiac deaths, and was significantly lower in patients with normal MPI, even after adjusting for other variables such as age [80 years, male gender, chest pain or dyspnea, hypertension, hyperlipidemia, diabetes mellitus, chronic kidney disease, atrial fibrillation, and abnormal ATP stress ECG. Each of the individual outcomes included in MACE was also significantly lower in patients with normal MPI. In addition, although patients aged C80 years had higher MACE rates than those aged 70-79 years when the summed stress score (SSS) was [8, the two groups had similar MACE rates when the SSS was B8. These results confirm the prognostic value of ATP-MPI in an elderly population with suspected CAD.The proportion of pharmacologic stress tests performed in the United States has steadily increased over the past several decades. Exercise stress testing is favored over vasodilator stress, since it is more physiological and since it assesses the functional capacity which provides important prognostic information.

Computed tomographic evaluation of myocardial ischemia

“…Regadenoson is a selective A2A agonist that has a lower risk of side effects. It is injected as a bolus of 0.4 mg over 10 s and is followed by a saline flush; it has a half-life of 33-108 s and is cleared by the kidney [23][24][25]. Patients should be instructed to avoid consuming caffeine-containing products for ≥ 24 h prior to the scheduled test to prevent the interference with the coronary vasodilatory effects.…”

New Algorithm of Stress Echocardiography with Adenosine Triphosphate

“…АТФ как вазодилататор может служить эффективным заменителем аденозина во время нагрузочных тестов -степень расширения коронарного русла, стабильность показателей кровотока в коронарных артериях, быстрое окончание действия (период полувыведения до 20 с), быстрота действия антидотов (эуфиллин) при использовании АТФ и аденозина приблизительно одинаковы [1,2,6,8,9,20,24]. К сожалению, публикации о применении АТФ в качестве стресс-агента при ЭхоКГ в нашей стране практически отсутствуют.…”

“…Ранее было продемонстрировано, что частота развития осложнений и их выраженность при нагрузочной пробе с АТФ намного ниже, чем при использовании добутамина, дипиридамола и аденозина [5,6,8,9]. В литературе не описано летальных исходов, случаев развития АВ-блока 3-й ст., желудочковой тахикардии, инфаркта миокарда, отека легких при стресс-тесте с АТФ.…”

“…А в отличие от аденозина, АТФ без труда может быть приобретен в российских аптеках. Сходство вазодилатирующего потенциала аденозина и АТФ обусловило достаточно широкое применение последнего в качестве стресс-агента при проведении динамической однофотонной эмиссионной компьютерной томографии (ОФЭКТ) и позитронно-эмиссионной томографии (ПЭТ) миокарда, перфузионной магнитно-резонансной томографии (ПМРТ) и перфузионной компьютерной томографии (ПКТ) коронарного русла в странах Юго-Восточной Азии и России [3][4][5][6][7][8].…”

Effect of aminophylline administration on the diagnostic yield of vasodilator myocardial perfusion imaging

“…2 The widespread utilization of regadenoson is supported by multiple factors including its similar diagnostic and prognostic performance to adenosine when used for MPI, the simpler and more rapid infusion protocol, and the better safety profile in specific patient groups. [3][4][5][6] Although better tolerated by patients, regadenoson shares with adenosine similar adverse effects such as flushing, headaches, and gastrointestinal symptoms. 3,7 Aminophylline, a nonselective adenosine receptor antagonist, has been available on the market for decades and used to reverse the adverse effects of dipyridamole and adenosine and more recently been shown to be safe and effective for use with regadenoson.…”