OBJECTIVES: The objective of this study is to evaluate the predictive value of the index of microcirculatory resistance (IMR) in patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Despite adequate epicardial artery reperfusion, a number of patients with STEMI have a poor prognosis because of microvascular damage. Assessing the status of the microvasculature in this setting remains challenging. METHODS: In 29 patients after primary PCI for STEMI, IMR was measured with a pressure sensor/thermistor-tipped guidewire. The Thrombolysis In Myocardial Infarction (TIMI) myocardial perfusion grade, TIMI frame count, coronary flow reserve, and ST-segment resolution were also recorded. RESULTS: The IMR correlated significantly with the peak creatinine kinase (CK) (R = 0.61, p = 0.0005) while the other measures of microvascular dysfunction did not. In patients with an IMR greater than the median value of 32 U, the peak CK was significantly higher compared with those having values <or=32 U (3,128 +/- 1,634 ng/ml vs. 1,201 +/- 911 ng/ml, p = 0.002). The IMR correlated significantly with 3-month echocardiographic wall motion score (WMS) (R = 0.59, p = 0.002) while the other measures of microvascular function did not. The WMS at 3-month follow-up was significantly worse in the group with an IMR >32 U compared with <or=32 U (28 +/- 7 vs. 20 +/- 4, p = 0.001). On multivariate analysis, IMR was the strongest predictor of peak CK and 3-month WMS. The IMR was the only significant predictor of recovery of left ventricular function on the basis of the percent change in WMS (R = 0.50, p < 0.01). CONCLUSIONS: Compared to standard measures, IMR appears to be a better predictor of microvascular damage after STEMI, both acutely and in short term follow-up.
OBJECTIVES: The objective of this study is to evaluate the predictive value of the index of microcirculatory resistance (IMR) in patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Despite adequate epicardial artery reperfusion, a number of patients with STEMI have a poor prognosis because of microvascular damage. Assessing the status of the microvasculature in this setting remains challenging. METHODS: In 29 patients after primary PCI for STEMI, IMR was measured with a pressure sensor/thermistor-tipped guidewire. The Thrombolysis In Myocardial Infarction (TIMI) myocardial perfusion grade, TIMI frame count, coronary flow reserve, and ST-segment resolution were also recorded. RESULTS: The IMR correlated significantly with the peak creatinine kinase (CK) (R = 0.61, p = 0.0005) while the other measures of microvascular dysfunction did not. In patients with an IMR greater than the median value of 32 U, the peak CK was significantly higher compared with those having values <or=32 U (3,128 +/- 1,634 ng/ml vs. 1,201 +/- 911 ng/ml, p = 0.002). The IMR correlated significantly with 3-month echocardiographic wall motion score (WMS) (R = 0.59, p = 0.002) while the other measures of microvascular function did not. The WMS at 3-month follow-up was significantly worse in the group with an IMR >32 U compared with <or=32 U (28 +/- 7 vs. 20 +/- 4, p = 0.001). On multivariate analysis, IMR was the strongest predictor of peak CK and 3-month WMS. The IMR was the only significant predictor of recovery of left ventricular function on the basis of the percent change in WMS (R = 0.50, p < 0.01). CONCLUSIONS: Compared to standard measures, IMR appears to be a better predictor of microvascular damage after STEMI, both acutely and in short term follow-up.
Authors: Mahmut Yesin; Metin Çağdaş; Macit Kalçık; Mahmut Uluganyan; Süleyman Çağan Efe; İbrahim Rencüzoğulları; Yavuz Karabağ; Mustafa Ozan Gürsoy; Süleyman Karakoyun Journal: Int J Cardiovasc Imaging Date: 2017-06-29 Impact factor: 2.357
Authors: Kathryn Dryer; Mark Gajjar; Nikhil Narang; Margaret Lee; Jonathan Paul; Atman P Shah; Sandeep Nathan; Javed Butler; Charles J Davidson; William F Fearon; Sanjiv J Shah; John E A Blair Journal: Am J Physiol Heart Circ Physiol Date: 2018-02-09 Impact factor: 4.733
Authors: Rahn Ilsar; Chirapan Chawantanpipat; Kim H Chan; Timothy A Dobbins; Richard Waugh; Annemarie Hennessy; David S Celermajer; Martin K C Ng Journal: PLoS One Date: 2010-03-09 Impact factor: 3.240