Myocardial bridging inasurvivor ofsudden cardiac near-death: role ofintracoronary Doppler flowmeasurements andangiography during dobutamine stress intheclinical evaluation

Extensive myocardial bridging intheleft anterior descending coronary arterywas foundina46yearoldsurvivor ofsudden cardiacnear-death. Positronemission tomography anddobutamine stress echocardiography revealed ischaemia inthe myocardiumdistal tothebridging. Spasm wasexcluded ascauseoftheischaemia by intracoronary infusion ofacetylcholine. Further evaluation ofthehaemodynamic importance ofthebridging usingintracoronary Dopplerflowvelocity measurementsrevealed anabnormalflowreserve. Dobutamine stress during coronary angiographycausedincreasedmechanical compression duringdiastole. Thiswas accompanied bymultiple premature ventricular contractions. Aftera debridging operation theflowvelocity reservewas normal.Theabnormalities foundduring dobutamine stress haddisappeared. Unexpectedly, a spasmwasinducible. This mayhavebeenduetolocal oedemaorscar formation aftertheoperation. Forthe evaluation ofthehaemodynamic importanceofmyocardial bridging, intracoronaryDopplerflowvelocity measurements