Abstract Background Revascularization of asymptomatic left main stenosis (LM) estimated by coronary angiography in the range of ambiguity (40-60%) necessitates further documentation by either intravascular imaging or fractional flow reserve. Distal left anterior descending artery velocity reserve (LADVR) by transthoracic Doppler echo has provided efficient prognostic yield for intermediate LAD lesions. Purpose Aim of the study was to assess the relationship between LADVR and LM stenosis and to evaluate the long-term cardiovascular outcome in patients with intermediate LM stenosis, following decision making for revascularization based on an efficient LADVR, on top of the dobutamine stress echo (DSE) result. Methods Eighty nine asymptomatic patients (age: 67±9 years, men/women: 70/19, ejection fraction EF: 52±6%, follow up: 50±25 months) were selected prospectively. They had an isolated intermediate stable LM stenosis (stenosis range 30-70%, with absence of hemodynamically significant LAD stenosis (<50%) and they were referred for DSE with a concomitant evaluation of LADVR after administration of adenosine. All patients had a negative DSE for ischemia with an estimated LADVR >2. Based on these data revasularization was deferred. Distribution of patients according to % LM stenosis was: LM 30-40%: 55 patients /LM 40-50%: 25 patients /LM50-60%: 6 patients /LM60-70%: 3 patients Results LADVR was not related to age or EF and was similar among LM increments: LM30-40%: 2.9±0.6 vs LM40-50%: 2.6±0.4 vs LM50-60%: 2.8±0.8 (distribution of values: figure1) A negative follow up for cardiac events was available in all patients. Moreover, 45 patients had an additional stress test negative for ischemia (either ECG or DSE/ SPECT) (LM30-40%: 30 patients, LM40-50%: 11patients, LM50-60: 2patients, LM60-70%: 2patients). LADVR was estimated during follow-up in 26±45 patients and it was <2 in 2 patients (both with a new significant LAD stenosis). Changes of LADVR during follow up compared to the initial LADVR were not related to LM stenosis ((% differences: figure2) Conclusion LADVR in the presence of an isolated LM disease is not related to the angiographically estimated stenosis. Moreover, evolution of LADVR is independent of the initial severity of LM stenosis. A negative DSE combined with adenosine LADVR>2 provides an efficient prognostic yield for a safe long-term outcome in isolated LM disease.
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