Study: Transthoracic echo sheds light on post-MI patients
The early measurement of coronary flow reserve (CRF) by transthoracic Doppler echocardiography can be of high value for the assessment of successful reperfusion in acute MI and can be used to predict left ventricular functional recovery, myocardial viability and the final infarct size, according to a study published online May 28 in Cardiovascular Ultrasound.
Egle Sadauskiene, MD, and colleagues of the department of cardiovascular medicine at Vilnius University Hospital Santariskiu Klinikos in Vilnius, Lithuania, sought to evaluate whether the preserved coronary flow reserve 72 hours after reperfused acute MI is associated with less microvascular dysfunction and is predictive of left ventricular functional recovery and the final infarct size at follow-up.
In the study, the researchers assessed CFR by transthoracic echo in 44 patients after a successful PCI during the acute AMI phase. CFR was correlated with contractile reserve assessed by low-dose dobutamine echocardiography and with the total perfusion defect measured by SPECT 72 hours after reperfusion and at five months follow-up.
The investigators estimated the CFR cut-off value of 1.75 as providing the maximal accuracy to distinguish between patients with preserved and impaired CFR during the acute AMI phase (sensitivity 91.7 percent, specificity 75 percent).
Also, the wall motion score index was better in the subgroup with preserved CFR as compared with the subgroup with reduced CFR: 1.74 versus 1.89 during the acute phase and 1.47 versus 1.81 at follow-up, respectively. Left ventricular ejection fraction was 47.78 percent in the preserved CFR group versus 40.79 percent in the impaired CFR group 72 hours after reperfusion and 49.78 percent versus 40.36 percent after five months at follow-up, respectively.
The final infarct size was smaller in patients with preserved as compared to patients with reduced CFR: 5.26 percent versus 23.28 percent at follow-up, the study authors reported.
While the researchers acknowledged that the relatively small number of patients was a study limitation, they noted that two subgroups were “quite homogeneous, so the results should be widely applicable.” They also said that their semi-quantitative analysis has some limitations when compared with PET or MRI with contrast (quantitative analysis of myocardial perfusion and viability).
“According to the data from our study, we can conclude that ECG ST-segment normalization of successful tissue reperfusion, but more extensive evaluation is necessary to estimate macrovascular integrity and to predict left ventricular functional recovery, the final infarct size and, consequently, a patient’s prognosis,” Sadauskiene and colleagues wrote.
They added that early CRF assessment by transthoracic echo provides information in patients who experienced a recent MI, and should be integrated into routine evaluation of these patients.
Egle Sadauskiene, MD, and colleagues of the department of cardiovascular medicine at Vilnius University Hospital Santariskiu Klinikos in Vilnius, Lithuania, sought to evaluate whether the preserved coronary flow reserve 72 hours after reperfused acute MI is associated with less microvascular dysfunction and is predictive of left ventricular functional recovery and the final infarct size at follow-up.
In the study, the researchers assessed CFR by transthoracic echo in 44 patients after a successful PCI during the acute AMI phase. CFR was correlated with contractile reserve assessed by low-dose dobutamine echocardiography and with the total perfusion defect measured by SPECT 72 hours after reperfusion and at five months follow-up.
The investigators estimated the CFR cut-off value of 1.75 as providing the maximal accuracy to distinguish between patients with preserved and impaired CFR during the acute AMI phase (sensitivity 91.7 percent, specificity 75 percent).
Also, the wall motion score index was better in the subgroup with preserved CFR as compared with the subgroup with reduced CFR: 1.74 versus 1.89 during the acute phase and 1.47 versus 1.81 at follow-up, respectively. Left ventricular ejection fraction was 47.78 percent in the preserved CFR group versus 40.79 percent in the impaired CFR group 72 hours after reperfusion and 49.78 percent versus 40.36 percent after five months at follow-up, respectively.
The final infarct size was smaller in patients with preserved as compared to patients with reduced CFR: 5.26 percent versus 23.28 percent at follow-up, the study authors reported.
While the researchers acknowledged that the relatively small number of patients was a study limitation, they noted that two subgroups were “quite homogeneous, so the results should be widely applicable.” They also said that their semi-quantitative analysis has some limitations when compared with PET or MRI with contrast (quantitative analysis of myocardial perfusion and viability).
“According to the data from our study, we can conclude that ECG ST-segment normalization of successful tissue reperfusion, but more extensive evaluation is necessary to estimate macrovascular integrity and to predict left ventricular functional recovery, the final infarct size and, consequently, a patient’s prognosis,” Sadauskiene and colleagues wrote.
They added that early CRF assessment by transthoracic echo provides information in patients who experienced a recent MI, and should be integrated into routine evaluation of these patients.