Effect of reactive hyperemia after coronary recanalization on myocardial tissue reperfusion by Thrombolysis In Myocardial Infarction flow grade in acute myocardial infarction

Atsunori Okamura, Hiroshi Ito, Katsuomi Iwakura, Shigeo Kawano, Toshiya Kurotobi, Motoo Date, Koichi Inoue, Toshio Ogihara, Kenshi Fujii

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Thrombolysis In Myocardial Infarction (TIMI) flow grade is widely used to evaluate myocardial tissue reperfusion in acute myocardial infarction (AMI), but the current grading system is incomplete. Therefore, we clarified the regulation of epicardial coronary flow velocity with the progression of microvascular dysfunction in AMI. We studied 36 patients with first anterior AMI. After intervention, we assessed TIMI flow grade and measured average peak velocity (APV) at baseline and after infusion of adenosine triphosphate (48 μg; baseline and hyperemic APVs, respectively) with a Doppler guidewire. We performed myocardial contrast echocardiography after 2 weeks to assess microvascular integrity (good reflow vs no reflow) and left ventriculography at admission and discharge (24 ± 2 days) to measure regional wall motion (SD/chord). Patients were classified into 3 groups based on TIMI flow grade and microvascular integrity: TIMI grade 3 flow/good reflow (n = 16), TIMI grade 3 flow/no reflow (n = 12), and TIMI grade 2 flow (n = 8). Baseline APV was comparable in the patients with TIMI grade 3 flow but hyperemic APV was higher in patients with TIMI grade 3 flow/good reflow than in those with TIMI grade 3 flow/no reflow (hyperemic APV 59.3 ± 25.8 vs 32.8 ± 8.9 cm/s, p <0.01). All patients with TIMI grade 2 flow showed no reflow and the lowest values of baseline and hyperemic APVs. Regional wall motion at discharge was higher in patients with TIMI grade 3 flow/good reflow than in those with TIMI grade 3 flow/no reflow and TIMI grade 2 flow (-1.44 ± 0.70, -2.69 ± 0.31, and -2.88 ± 0.48 SD/chord, respectively, p <0.01). In conclusion, compensatory reactive hyperemia preserves epicardial coronary flow velocity even in patients with microvascular damage, and with the progression of damage, this compensatory hyperemia can no longer preserve epicardial coronary flow velocity, and baseline APV is decreased in TIMI grade 2 flow.

Original languageEnglish
Pages (from-to)617-623
Number of pages7
JournalAmerican Journal of Cardiology
Volume97
Issue number5
DOIs
Publication statusPublished - Mar 1 2006
Externally publishedYes

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

Fingerprint Dive into the research topics of 'Effect of reactive hyperemia after coronary recanalization on myocardial tissue reperfusion by Thrombolysis In Myocardial Infarction flow grade in acute myocardial infarction'. Together they form a unique fingerprint.

  • Cite this