Evaluation of heart function with impedance cardiography in acute myocardial infarction patients.

Unlabelled: To evaluate the capability of impedance cardiography (ICG) in reflecting the cardiac functions of acute myocardial infarction (AMI) patients.

Methods: 99 inpatients with initial AMI were recruited. Venous blood was obtained for detection of N-terminal brain-type natriuretic peptide (NT-proBNP), B-Type natriuretic peptide (BNP) and c troponin-T (cTnT) followed by ICG. Thorax fluid capacity (TFC), pre-ejection period (PEP), left ventricular ejection fraction (LVEF), cardiac output (CO), stroke volume (SV), stroke index (SI), systemic vascular resistance (SVR), systemic vascular resistance index (SVRI), cardiac index (CI), end-diastolic volume (EDV) and systolic time ratio (STR) were measured. All these patients underwent ICG and echocardiography 2 days after surgery.

Results: Our results indicated NT-proBNP and BNP were associated with SVR, SVRI, PEP and STR, independently (P < 0.05). cTnT was associated with SVR and SVRI (P < 0.05). And the outcomes showed correlation between ICG and echocardiography in SV, SI, EDV, LEVT, STR, LVEF (P < 0.01), CO and CI (P < 0.05). However, no correlation was noted in PEP. In addition, changes were also found in the blood pressure and heart rate 7 days after PCI.

Conclusion: May be ICG data could reflect the early cardiac functions of AMI patients, but the accuracy of ICG in evaluating cardiac functions should be combined with detection of blood NT-proBNP, BNP and cTnT and echocardiography.