title: Prognostic value of microvascular resistance index immediately after primary percutaneous coronary intervention on left ventricular remodeling in patients with reperfused anterior acute ST-segment elevation myocardial infarction.
abstract: OBJECTIVE
  This study sought to investigate the relationship between the degree of microvascular dysfunction assessed by a dual-sensor guidewire (pressure and Doppler velocity) and left ventricular (LV) remodeling after successful primary percutaneous coronary intervention (PPCI) for a first anterior acute myocardial infarction (AMI).
  
  
  BACKGROUND
  Microvascular dysfunction after AMI is associated with progressive LV dilation.
  
  
  METHODS
  In 24 consecutive patients, the microvascular resistance index (MVRI) immediately after PPCI was calculated as the ratio of the mean distal pressure to average peak flow velocity during maximal hyperemia. Cardiac magnetic resonance was performed to determine LV volumes at baseline and 8-month follow-up. LV remodeling was defined as an increase in left ventricular end-diastolic volume (LVEDV) of ≥20%.
  
  
  RESULTS
  In patients with an MVRI greater than the median value of 2.96 mm Hg·cm(-1)·s, the LVEDV increased significantly from 117.1 ± 20.7 ml at baseline to 146.5 ± 21.4 ml (p = 0.006) at 8 months, whereas it did not change between baseline and 8 months (108.2 ± 21.2 ml vs. 111.6 ± 29.9 ml, p = 0.620) in patients with an MVRI ≤2.96 mm Hg·cm(-1)·s. LV remodeling was more frequent in the group with an MVRI >2.96 mm Hg·cm(-1)·s (64% vs. 15%, p = 0.033). Furthermore, there was a positive correlation between MVRI and the percentage of increase or decrease in LVEDV (r = 0.42, p = 0.042). Logistic regression analysis showed that MVRI was the strongest univariate predictor of LV remodeling. The best cutoff value of MVRI was 2.96 mm Hg·cm(-1)·s with a sensitivity of 78% and a specificity of 73%.
  
  
  CONCLUSIONS
  MVRI immediately after PPCI predicts LV remodeling in patients with reperfused anterior AMI.
authors.affiliation: Department of Cardiovascular Medicine, Wakayama Medical University, Wakayama, Japan. Electronic address: hkitaba@wakayama-med.ac.jp.
authors.forename: Hironori
authors.initials: H
authors.lastname: Kitabata
authors.forename: Takashi
authors.initials: T
authors.lastname: Kubo
authors.forename: Kohei
authors.initials: K
authors.lastname: Ishibashi
authors.forename: Kenichi
authors.initials: K
authors.lastname: Komukai
authors.forename: Takashi
authors.initials: T
authors.lastname: Tanimoto
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ino
authors.forename: Manabu
authors.initials: M
authors.lastname: Kashiwagi
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ozaki
authors.forename: Yasutsugu
authors.initials: Y
authors.lastname: Shiono
authors.forename: Kunihiro
authors.initials: K
authors.lastname: Shimamura
authors.forename: Makoto
authors.initials: M
authors.lastname: Orii
authors.forename: Kumiko
authors.initials: K
authors.lastname: Hirata
authors.forename: Atsushi
authors.initials: A
authors.lastname: Tanaka
authors.forename: Toshio
authors.initials: T
authors.lastname: Imanishi
authors.forename: Takashi
authors.initials: T
authors.lastname: Akasaka
mesh_terms: D000368:Aged; D056988:Anterior Wall Myocardial Infarction / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D001783:Blood Flow Velocity; D003326:Coronary Circulation; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D016017:Odds Ratio; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects; D011237:Predictive Value of Tests; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014655:Vascular Resistance; D016277:Ventricular Function, Left; D020257:Ventricular Remodeling
keywords: AMI; CFR; CK-MB; CMR; LV; LVEDV; MVD; MVO; MVRI; PPCI; Pa; Pd; TIMI; Thrombolysis In Myocardial Infarction; acute myocardial infarction; aortic pressure; cardiac magnetic resonance; coronary flow reserve; creatine kinase-myocardial band; distal pressure; left ventricle/ventricular; left ventricular end-diastolic volume; left ventricular remodeling; microvascular dysfunction; microvascular obstruction; microvascular resistance index; primary percutaneous coronary intervention