Coronary microvascular dysfunction after elective percutaneous coronary intervention: correlation with exercise stress test results.
OBJECTIVE
We assessed whether exercise stress test (EST) results are related to the presence of coronary microvascular dysfunction (CMVD) in patients undergoing elective percutaneous coronary intervention (PCI).


BACKGROUND
Previous studies showed that EST is poorly reliable in predicting restenosis after PCI; some studies also showed CMVD in the territory of the treated vessel.


METHODS
We studied 29 patients (age 64 ± 6, 23 M) with stable coronary artery disease and isolated stenosis (>75%) of the left anterior descending (LAD) coronary artery, undergoing successful PCI with stent implantation. EST and assessment of coronary microvascular function were performed 24h, 3 months and 6 months after PCI. Coronary blood flow (CBF) response to adenosine and to cold-pressor test (CPT) was assessed in the LAD coronary artery by transthoracic Doppler echocardiography.


RESULTS
Patients with ST-segment depression ≥ 1 mm at EST performed 24h after PCI (n=11, 38%) showed a lower CBF response to adenosine compared to those with negative EST (1.65 ± 0.4 vs. 2.11 ± 0.4, respectively, p=0.003), whereas the difference in CBF response to CPT was not significant (1.44 ± 0.4 vs. 1.64 ± 0.3, respectively; p=0.11). At 3-month and 6-month follow-up a positive EST was found in 12 (41%) and 13 (44%) patients, respectively; patients with positive EST also had lower CBF response to adenosine compared to those with negative EST (3 months: 1.69 ± 0.3 vs. 2.20 ± 0.3, respectively; 6 months: 1.66 ± 0.2 vs. 2.32 ± 0.3, respectively; p<0.001 for both).


CONCLUSIONS
Positive EST after elective successful PCI consistently reflects impairment of hyperemic CBF due to CMVD, which persists over a follow-up period of 6 months.
Institute of Cardiology, Università Cattolica del Sacro Cuore, Roma, Italy.
Maria
M
Milo
Roberto
R
Nerla
Pierpaolo
P
Tarzia
Fabio
F
Infusino
Irma
I
Battipaglia
Alfonso
A
Sestito
Gaetano Antonio
GA
Lanza
Filippo
F
Crea
D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D003326:Coronary Circulation / Q000502:physiology*; D017558:Elective Surgical Procedures / Q000009:adverse effects* / Q000639:trends; D005080:Exercise Test / Q000379:methods* / Q000639:trends; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D055806:Microvessels / Q000503:physiopathology*; D008875:Middle Aged; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects* / Q000639:trends