Myocardial bridging is an independent predictor of positive spasm provocation testing by intracoronary ergonovine injections: a retrospective observational study

Figures

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  Fig. 1. Flowchart for the patient selection. CAG coronary angiography, SPT spasm provocation test, LAD left anterior descending coronary artery, PCI percutaneous coronary intervention, MB myocardial bridging, ACH acetylcholine

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  Fig. 2. A representative case with MB and SPT-positivity in the LAD on the coronary angiogram at baseline (a–c), before (d, e), and after the SPT (f). At baseline and before the ER injections, the LCA angiogram shows no stenosis during the end-diastole phase (a, d) but MB is observed in the mid-LAD, as shown by squeezing (arrow heads) during the end-systole phase (b, e). The RCA angiogram shows no organic stenosis (c). After the ER injections, the LAD becomes a total occlusion at the proximal lesion (f). After the ER injections into the LCA, the chest pain and ECG changes persist and nitrates are required to relieve the vasospasms, and therefore, SPT in the RCA was not performed. In this case, the culprit vessel of the SPT-positivity was the LAD, and the positional relationship of the vasospasms to the MB was the “segment proximal to the MB” (f). CAG coronary angiography, SPT spasm provocation test, ER ergonovine, LAD left anterior descending coronary artery, RCA right coronary artery, ECG electrocardiogram

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  Fig. 3. A representative case with MB and a spastic vessel (SPT-negativity) in the LAD but with SPT-positivity in the RCA on the coronary angiogram at baseline (a, b), before (c, d, f) and after the SPT (e, g). At baseline and before the ER injections, the LCA angiogram shows no organic stenosis during the end-diastole phase (a, c), but MB in the mid-LAD is observed as shown by the squeezing (arrow heads) during the end-systole phase (b, d). After the ER injections in the LCA, the LAD exhibits severe stenosis without a delay (e), but no ECG changes or chest symptoms occur. Before the ER injections into the RCA, no stenosis is observed (f), but the ER injections cause a subtotal occlusion (g). In this case, the culprit vessel of the SPT-positivity was the RCA, even though the LAD was a spastic vessel, suggesting a certain degree of endothelial dysfunction in the LAD. CAG coronary angiography, SPT spasm provocation test, ER ergonovine, LAD left anterior descending coronary artery, LCA left coronary artery, RCA right coronary artery, ECG electrocardiogram

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  Fig. 4. A representative case with MB and SPT-negativity in the LAD but with SPT-positivity in the RCA on the coronary angiogram before (a–c) and after the SPT (c, f). Before the ER injections, the LCA angiogram shows no significant stenosis during end-diastole (a) but MB in the mid-LAD is observed as shown by the “squeezing” (arrow heads) (b). After the ER injections into the LCA, the LAD does not have any spastic changes (c). Before the ER injection in the RCA, no stenosis was observed (e), but the ER injections cause a subtotal occlusion (f). In this case, the culprit vessel of the SPT-positivity was the RCA. CAG coronary angiography, SPT spasm provocation test, ER ergonovine, LCA left coronary artery, LAD left anterior descending coronary artery, RCA right coronary artery

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  Fig. 5. A representative case with diffuse MB in the LAD and multivessel spasms on the coronary angiogram before (a, b, f) and after the SPT (c–e, g). Before the ER injections, the LCA exhibits no stenosis during end-diastole (a), but MB in the mid-LAD is observed as shown by the “squeezing” (arrow head) (b). After the ER injections in the LCA, both the LAD and LCX show a subtotal occlusion with a delay (c, e), and chest pain and ECG changes occur. Thereafter, the chest pain and ECG changes improved without using nitrate infusions (d), so the SPT of the RCA was continued and no significant stenosis was observed (f). The ER injections in the RCA cause a total occlusion (g). In this case, the culprit vessels of the SPT-positivity were the RCA, LAD, and LCX. The positional relationship of the vasospasms to the MB segment was “diffuse, namely the segments proximal to the MB, on the MB, and distal to the MB” (c, e). CAG coronary angiography, SPT spasm provocation test, ER ergonovine, LCA left coronary artery, LAD left anterior descending coronary artery, RCA right coronary artery, LCX left circumflex artery, ECG electrocardiogram