Brachial artery low-flow-mediated constriction is increased early after coronary intervention and reduces during recovery after acute coronary syndrome: characterization of a recently described index of vascular function.

AIMS: The endothelium plays a role in regulating vascular tone. Acute and dynamic changes in low-flow-mediated constriction (L-FMC) and how it changes with regard to traditional flow-mediated dilatation (FMD) have not been described. We aimed to investigate the changes in brachial artery L-FMC following percutaneous coronary intervention (PCI) and during recovery from non-ST-segment elevation myocardial infarction (NSTEMI). METHODS AND RESULTS: FMD was performed in accordance with a previously described technique in patients before and after PCI and in the recovery phase of NSTEMI, but in addition, L-FMC data were acquired from the last 30 s of cuff inflation. About 135 scans were performed in 96 participants (10 healthy volunteers and 86 patients). Measurement of brachial L-FMC was reproducible over hours. L-FMC was greater among patients with unstable vs. stable coronary atherosclerosis (-1.33 ±1.09% vs. -0.03 ± 1.26%, P < 0.01). Following PCI, FMD reduced (4.43 ± 2.93% vs. 1.66 ± 2.16%, P < 0.01) and L-FMC increased (-0.33 ± 0.76% vs. -1.63 ± 1.15%, P = 0.02). Furthermore, during convalescence from NSTEMI, L-FMC reduced (-1.37 ± 1.19% vs. 0.01 ± 0.82%, P = 0.02) in parallel with improvements in FMD (2.54 ± 2.19% vs. 5.15 ± 3.07%, P < 0.01). CONCLUSION: Brachial L-FMC can be measured reliably. Differences were observed between patients with stable and unstable coronary disease. L-FMC was acutely increased following PCI associated with reduced FMD and, in the recovery from NSTEMI, L-FMC reduced associated with increased FMD. These novel findings characterize acute and subacute variations in brachial L-FMC. The pathophysiological and clinical implications of these observations require further study.

Ruptured sinus of Valsalva aneurysm presenting as ST-elevation myocardial infarction.

BACKGROUND: A 52-year-old man presented with central chest pain, which he had experienced for 8 h. He had no other associated symptoms and no prior history of cardiovascular disease. INVESTIGATIONS: Electrocardiography, chest radiography, coronary angiography, aortic angiography, echocardiography, CT thorax with contrast. DIAGNOSIS: Ruptured aneurysm of the sinus of Valsalva. MANAGEMENT: Emergency sternotomy and pericardiotomy, followed by aortic root replacement.

Percutaneous coronary intervention of a circumflex chronic total occlusion using an epicardial collateral retrograde approach.

Antegrade disobliteration of a chronic total coronary occlusion (CTO) may be technically difficult in spite of the use of customized equipment. Retrograde approaches via intramyocardial septal or bypass grafts have been described. We report a successful Percutaneous intervention of a proximal circumflex CTO using a retrograde approach via an epicardial collateral.