Minako Ohara

Four-year clinical outcomes of the OLIVUS-Ex (impact of Olmesartan on progression of coronary atherosclerosis: Evaluation by intravascular ultrasound) extension trial

BACKGROUND The previous OLIVUS trial reported a positive role in achieving a lower rate of coronary atheroma progression through the administration of olmesartan, an angiotension-II receptor blocking agent (ARB), for stable angina pectoris (SAP) patients requiring percutaneous coronary intervention (PCI). However, the benefits between ARB administration on long-term clinical outcomes and serial atheroma changes by IVUS remain unclear. Thus, we examined the 4-year clinical outcomes from OLIVUS according to treatment strategy with olmesartan. METHODS Serial volumetric IVUS examinations (baseline and 14 months) were performed in 247 patients with hypertension and SAP. When these patients underwent PCI for culprit lesions, IVUS was performed in their non-culprit vessels. Patients were randomly assigned to receive 20-40mg of olmesartan or control, and treated with a combination of β-blockers, calcium channel blockers, glycemic control agents and/or statins per physicians guidance. Four-year clinical outcomes and annual progression rate of atherosclerosis, assessed by serial IVUS, were compared with major adverse cardio- and cerebrovascular events (MACCE). RESULTS Cumulative event-free survival was significantly higher in the olmesartan group than in the control group (p=0.04; log-rank test). By adjusting for validated prognosticators, olmesartan administration was identified as a good predictor of MACCE (p=0.041). On the other hand, patients with adverse events (n=31) had larger annual atheroma progression than the rest of the population (23.8% vs. 2.1%, p<0.001). CONCLUSIONS Olmesartan therapy appears to confer improved long-term clinical outcomes. Atheroma volume changes, assessed by IVUS, seem to be a reliable surrogate for future major adverse cardio- and cerebrovascular events in this study cohort.

Nicorandil prevents microvascular dysfunction resulting from PCI in patients with stable angina pectoris: a randomised study

AIMS Nicorandil, an ATP sensitive potassium channel opener, may reduce the incidence of microvascular dysfunction after percutaneous coronary intervention (PCI) by dilating coronary resistance vessels. The aim of the study was evaluation of the impact of the administration of intravenous nicorandil on measuring the index of microcirculatory resistance (IMR) in PCI to patients with stable angina pectoris (SAP). METHODS AND RESULTS Intravascular ultrasound (IVUS), fractional flow reserve (FFR), IMR and blood examination (CK-MB), cardiac troponin I (cTnI) immediately post-PCI (and 24 hours later) were performed in 62 consecutive patients with SAP undergoing PCI. FFR and IMR were measured simultaneously with a single coronary pressure wire. IMR was defined as Pd/coronary flow (or Pd* mean transit time) at peak hyperaemia. Patients were randomised to the control (n=29), or nicorandil group (n=33). In the nicorandil group, nicorandil was intravenously administered as a 6 mg bolus injection just before PCI and as a constant infusion at 6 mg/hour for 24 hours thereafter. All volumetric IVUS parameters and FFR were similar between the two groups both pre- and post-PCI. However, IMR immediately post-PCI and cTnI 24 hours post-PCI were significantly higher in the control group compared to the nicorandil group (IMR: 25.4±12.1 vs. 17.9±9.1 units, and cTnI: 0.21±0.13 vs. 0.12±0.08 ng/mL, for control vs. nicorandil). The incidence for cTnI elevation more than fivefold the normal range (>0.20 ng/mL) was significantly larger in the control group than in the nicorandil group (41% vs. 12%, p<0.01). Additionally, the control group showed a closer correlation between plaque volume reduction during stenting as assessed by volumetric IVUS, and cTnI elevation than the nicorandil group (r=0.55 vs. 0.42, p<0.001 for control vs. nicorandil). CONCLUSIONS In patients undergoing successful coronary stenting for stable angina, administration of nicorandil is associated with reduced microvascular dysfunction induced by PCI.

Efficacy and Accuracy of Novel Automated Mitral Valve Quantification: Three-Dimensional Transesophageal Echocardiographic Study

Previous studies indicated that the three‐dimensional features of the mitral valve (MV) have a significant impact on MV disease. However, quantification of MV with manual tracing software was too time‐consuming for routine clinical practice. This study was performed to investigate the efficacy and accuracy of MV quantification with a novel highly automated commercially available software package developed for this purpose.

Insufficient Leaflet Remodeling in Patients With Atrial FibrillationCLINICAL PERSPECTIVE: Association With the Severity of Mitral Regurgitation

Background— The relationship between annular dilatation caused by atrial fibrillation (AF) and mitral regurgitation (MR) remains controversial. We hypothesized that the small ratio of total leaflet area/annulus area (TLA/AA), reflecting insufficient leaflet remodeling to annular dilatation, is a main component of MR in patients with AF. Methods and Results— Three-dimensional transesophageal echocardiographic data of the mitral valve were analyzed in 28 AF patients with moderate or severe MR (MR group), age- and sex-matched 56 AF patients with mild or less MR (non-MR group), and 16 control subjects. AA was significantly greater in both the MR (645±126 mm2/m2, P<0.001) and non-MR groups (568±121 mm2/m2, P=0.001) compared with control subjects (444±108 mm2/m2). However, TLA/AA was significantly smaller in the MR (1.29±0.10, P<0.001), but not in the non-MR group (1.65±0.24, P>0.99), compared with control subjects (1.70±0.29). In linear regression analysis, TLA/AA was inversely associated with the effective regurgitant orifice (r=−0.73, P<0.001). The area under the receiver-operating-characteristics curve of TLA/AA was significantly greater than that of AA (0.95 versus 0.72, P<0.001). Multivariable analysis revealed that small TLA/AA (P<0.001) was independently associated with significant MR, while AA was not (P=0.26). Conclusions— In patients with AF, insufficient leaflet remodeling to annular dilatation, rather than crude annular dilatation, was strongly associated with the severity of MR.

Relationship between Myocardial Flow Reserve by Oxygen-15 Water Positron Emission Tomography in the Subacute Phase of Myocardial Infarction and Left Ventricular Remodeling in the Chronic Phase

The purposes of this study were to examine the effects of angiotensin-converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) on myocardial flow reserve in patients with acute myocardial infarction (AMI) in the subacute phase using oxygen-15 positron emission tomography (PET) and to elucidate the relationship between the myocardial flow reserve and remodeling in the chronic phase. Sixty patients who had been treated with coronary angioplasty within 12 h after the onset of AMI were enrolled. Patients were divided into an enalapril (ACEI) group and a candesartan (ARB) group. The myocardial flow reserve was measured by oxygen-15 water PET in the subacute phase from the 20th to the 30th day after the onset of AMI. Left ventriculography was performed to measure the left ventricular ejection fraction in the chronic phase about 6 months after the onset. Ten patients (33%) in the enalapril group and 4 patients (13%) in the candesartan group stopped taking their respective medications within a few days of starting, because of side effects such as cough or hypotension. Thus, the prevalence of medication intolerance was higher in the enalapril group. The myocardial flow reserve in the subacute phase and the left ventricular ejection fraction in the chronic phase were lower in the enalapril group (2.08±0.30 and 42±6%) than in the candesartan group (2.25±0.20 and 49±5%) (p<0.05). The myocardial flow reserve significantly correlated with the left ventricular ejection fraction in all patients (r=0.45, p<0.01). The myocardial flow reserve assessed by PET in the subacute phase after AMI was found to be related to left ventricular remodeling in the chronic phase.

Prolapse Volume to Prolapse Height Ratio for Differentiating Barlow’s Disease From Fibroelastic Deficiency

BACKGROUND As mitral valve (MV) repair for Barlows disease remains surgically challenging, it is important to distinguish Barlows disease from fibroelastic deficiency (FED) preoperatively. We hypothesized that the prolapse volume to prolapse height ratio (PV-PH ratio) may be useful to differentiate Barlows disease and FED.Methods and Results:In 76 patients with MV prolapse who underwent presurgical transesophageal echocardiography, the 3D MV morphology was quantified: 19 patients were diagnosed with Barlows disease and 57 with FED. The patients with Barlows disease had greater prolapse volume and height than the patients with FED, as well as greater PV-PH ratio (0.61±0.35 vs. 0.17±0.10, P<0.001). Receiver-operating characteristic analysis revealed that with a cutoff value of 0.27, the PV-PH ratio differentiated Barlows disease from FED with 84.2% sensitivity and 84.2% specificity. Net reclassification improvement showed that the differentiating ability of the PV-PH ratio was significantly superior to prolapse volume (1.30, P<0.001). After being adjusted by each of prolapse volume and height, annular area and shape, and the number of prolapsed segments, the PV-PH ratio had an independent association with Barlows disease. CONCLUSIONS The PV-PH ratio was able to differentiate Barlows disease from FED with high accuracy. 3D quantification including this value should be performed before MV repair.