Scintigraphic Evaluation of Contractile and Coronary Reserve in Patients With Ischemic Cardiomyopathy

Before surgical intervention, all patients pass routine clinical analyzes undergo coronary angiography and 2D echocardiography. Some of patients in the ICM-1 and ICM-2 groups undergo stress echocardiography with dobutamine.

Coronary arteriography is performed using the Axiom Artis (Siemens; Erlangen, Germany) and transthoracic two-dimensional Doppler echocardiography (TTE) with the Acuson Sequoia 512 (Siemens; Erlangen, Germany)).

Besides, all of the ICM-1 and ICM-2 groups patients undergo myocardial perfusion imaging. Standard two-day stress-rest imaging protocol is used. Adenosine at a dosage of 140 mcg/kg/min (for 4 min) is used as a pharmaceutical stress agent.

ICM-1 group and Control group for GBPS undergo gated blood pool SPECT (GBPS) at rest and during increasing doses of dobutamine (5/10/15 μg/kg/min) (n = 60) ICM-2 group and Control group for CFR undergo dynamic SPECT (n = 40). This investigation is combined with routine myocardial perfusion imaging so patients are not exposed to extra stress.

Than ICM patients undergo surgical treatment of ICM in different volume. All of them receive coronary bypass grafting (CABG); some patients undergo the left ventricular reconstruction and intervention on the mitral valve.

In the early postoperative period (7-14 days), the ICM-1 group undergo rest GBPS and ICM-2 group undergo dynamic SPECT by two-day protocol. All patients undergo TTE too.

After at least 12 month, all patients undergo TTE to assess the presence of left ventricular (LV) remodeling.

Inclusion criteria

А) For ICM group:

• History of myocardial infarction (MI) or revascularization (CABG or PCI);
• > 75% stenosis of left main or proximal LAD and/ or stenosis of > 75% of ≥2 epicardial vessels (based on coronary angiography (CA) data);
• LV EF <40% and increase in LV volumes according to echocardiography (ECHO)

B) For GBPS Control group

• Absence of obstructive coronary artery lesion;
• Absence of history of MI and revascularization.

C) For CFR Control group

• Presence of obstructive coronary artery lesion;
• Indications for coronary artery bypass grafting;

Exclusion criteria

(for all groups):

• Presence of contraindications to the stress test with inotropic stimulation;
• Inflammatory myocardial diseases;
• The presence of severe hematological, neurological disorders, other psychosomatic conditions that impede research;
• Life expectancy of less than 6 months (acute renal and hepatic failure, mental illness, malignant neoplasms of the final stages, unsuitable correction of brain injury).