Assessment of optimum stent deployment by stent boost imaging: comparison with intravascular ultrasound.

Stent boost (SB) imaging is an enhancement of the radiologic edge of the stent by digital management of regular X-ray images. The purpose of the present study was to validate SB imaging by comparison with the anatomical standard using intravascular ultrasound (IVUS). We investigated SB and IVUS after stent implantation in 68 arteries in 60 patients. Based on those findings, we added high-pressure dilatation in four patients and another stent implantation in four patients. We defined the SB criteria for adequate stent deployment as: complete stent expansion, stent minimum diameter ≥70% of reference diameter, and stent minimum diameter ≥2.0 mm; and IVUS criteria for adequate stent deployment as: minimal stent area ≥5.0 mm(2). If the reference vessel was <2.8 mm, adequate stent deployment was defined as minimum stent area ≥4.5 mm(2). IVUS findings indicated inadequate stent deployment in 21/72 observations (29%). Seven SB images showed inadequate stent expansion. SB predicted inadequate findings of IVUS with 100% specificity, 33% sensitivity, and 81% agreement. Although the sensitivity of SB image for adequate stent deployment is low, the specificity is sufficiently high for it to be the first-line for monitoring just after stent implantation in centers where IVUS is not used routinely.

Type B aortic dissection resulting in acute esophageal necrosis.

In the present article, we report a case in which acute esophageal necrosis (AEN) of the intrathoracic esophagus was caused by extensive thrombosis in the false lumen of an aortic dissection, thereby occluding the blood flow to the intercostal arteries and thus the esophagus. According to the previously published data, AEN after aortic dissection is very rare and usually fatal. Besides esophageal ischemia secondary to arterial occlusion, direct extrinsic compression of the arteriovenous network surrounding the esophagus, caused by the traumatic pathology of the aorta, by extensive extravasation may also cause AEN. AEN is most commonly confirmed by esophagoscopy, typically showing a black, diffusely necrotic, and ulcerated esophageal mucosa.

Effect of phentolamine on the hyperemic response to adenosine in patients with microvascular disease.

For accurate measurement of the fractional flow reserve (FFR) of the myocardium, the presence of maximum hyperemia is of paramount importance. It has been suggested that the hyperemic effect of the conventionally used hyperemic stimulus, adenosine, could be submaximal in patients who have microvascular dysfunction and that adding alpha-blocking agents could augment the hyperemic response in these patients. We studied the effect of the nonselective alpha-blocking agent phentolamine, which was administered in addition to adenosine after achieving hyperemia, in patients who had microvascular disease and those who did not. Thirty patients who were referred for percutaneous coronary intervention were selected. Of these 30 patients, 15 had strong indications for microvascular disease and 15 did not. FFR was measured using intracoronary adenosine, intravenous adenosine, and intracoronary papaverine before and after intracoronary administration of the nonselective alpha blocker phentolamine. In patients who did not have microvascular disease, no differences in hyperemic response to adenosine were noted, whether or not alpha blockade was given before adenosine administration; FFR levels before and after phentolamine were 0.76 and 0.75, respectively, using intracoronary adenosine (p = 0.10) and 0.75 and 0.74, respectively, using intravenous adenosine (p = 0.20). In contrast, in patients who had microvascular disease, some increase in hyperemic response was observed after administration of phentolamine; FFR levels decreased from 0.74 to 0.70 using intracoronary adenosine (p = 0.003) and from 0.75 to 0.72 using intravenous adenosine (p = 0.04). Although statistically significant, the observed further decrease in microvascular resistance after addition of phentolamine was small and did not affect clinical decision making in any patient. In conclusion, when measuring FFR, routinely adding an alpha-blocking agent to adenosine does not affect clinical decision making.

Long-term clinical outcome after fractional flow reserve-guided percutaneous coronary intervention in patients with multivessel disease.

OBJECTIVES: In the present study, we analyzed the clinical outcome of patients with multivessel coronary artery disease in whom at least one vessel was treated by percutaneous coronary intervention (PCI) and at least one other vessel was deferred on the basis of fractional flow reserve (FFR) measurements during the same session. BACKGROUND: Myocardial FFR is an established tool for assessing the severity of epicardial stenoses. It has been shown that it is safe to defer an intervention in single vessel disease patients when FFR >0.75. METHODS: One hundred two patients (66 +/- 10 years) with multivessel coronary artery disease were included in the study. In all patients, PCI of at least two vessels was contemplated. Yet in all of them at least one vessel was treated by PCI, whereas at least one other vessel was deferred based on an FFR >0.75. Major adverse cardiac events (MACE) were recorded during an average follow-up of 29 +/- 18 months. RESULTS: In 102 patients, 113 coronary arteries underwent PCI. In these arteries FFR was 0.57 +/- 0.13 and mean diameter stenosis was 68 +/- 14%. One hundred twenty-seven coronary arteries had an FFR >0.75 and PCI was deferred. In these arteries FFR was 0.86 +/- 0.06 and mean diameter stenosis was 47 +/- 12%. No death occurred during the follow-up. A MACE occurred in 9% and 13% of patients after 12 and 36 months, respectively. These MACE were related to 22 (9.2%) arteries. Among them, 8 (6.3%) MACE were related to one of the initially deferred vessels, whereas 14 (12.3%) MACE were related to one of the initially treated coronary artery. CONCLUSIONS: In patients with multivessel disease, PCI of hemodynamically non-significant stenoses can be safely deferred, even if initially planned on the basis of the angiogram.

Percutaneous coronary intervention or bypass surgery in multivessel disease? A tailored approach based on coronary pressure measurement.

The optimal revascularization strategy, percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG), for patients with multivessel coronary artery disease (MVD) remains controversial. The aim of the present study was to compare the long-term outcomes after selective PCI of only hemodynamically significant lesions (fractional flow reserve, or FFR < 0.75) to CABG of all stenoses in patients with MVD. In 150 patients with MVD referred for CABG, FFR was determined in 381 coronary arteries considered for bypass grafting. If the FFR was less than 0.75 in three vessels or in two vessels including the proximal left anterior descending (LAD) artery, CABG was performed (CABG group). If only one or two vessels were physiologically significant (not including the proximal LAD), PCI of those lesions was performed (PCI group). Of the 150 patients, 87 fulfilled the criteria for CABG and 63 for PCI. There were no significant differences in the angiographic or other baseline characteristics between the two groups. At 2-year follow-up, no differences were seen in adverse events, including repeat revascularization (event-free survival 74% in the CABG group and 72% in the PCI group). A similar number of patients were free from angina (84% in the CABG group and 82% in the PCI group). Importantly, the results in both groups were as good as the surgical groups in previous studies comparing PCI and CABG in MVD. In patients with multivessel disease, PCI in those with one or two hemodynamically significant lesions as identified by an FFR < 0.75 yields a similar favorable outcome as CABG in those with three or more culprit lesions despite a similar angiographic extent of disease.

False-negative myocardial scintigraphy in balanced three-vessel disease, revealed by coronary pressure measurement.

In nuclear perfusion imaging of the myocardium, a false-negative test result in patients with balanced three-vessel disease is a well-known pitfall. This paper describes a patient with typical chest pain and a negative myocardial perfusion scintigram. At coronary angiography, intermediate stenoses in the left anterior descending (LAD), left circumflex (LCX), and right coronary (RCA) arteries were present. Fractional flow reserve, measured by coronary pressure measurement, was 0.54, 0.56, and 0.66 respectively for the LAD, LCX, and RCA, unequivocally demonstrating the presence of balanced three-vessel disease. The patient underwent successful bypass surgery and remained event-free thereafter.