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BACKGROUND: The treatment of a coronary bifurcation with a single stent (the provisional stenting technique) is associated with a good outcome in most cases. In the majority of cases, after provisional stenting technique, a residual significant angiographic stenosis is associated with the absence of ischemia when fractional flow reserve (FFR) is measured. Jailing an optical pressure guidewire in the side branch (SB) could potentially reduce unnecessary SB interventions after provisional stenting technique. The aim of this study was to compare distal pressure to aortic pressure ratio (Pd/Pa) measurements between 2 second-generation optical pressure guidewires in bifurcation treatment-a jailed wire (JW) and a second free-floating wire (FW) advanced into the SB after stenting. METHODS: In an in vitro bifurcation hydrodynamic model with pressure sensors, a JW was advanced into the SB and the FW into the main branch. Bifurcation stenting is performed with the proximal optimization technique (POT)-side-POT technique using a 3.0 x 22-mm stent, a 4.0 x 12-mm noncompliant balloon for the POT, and a 2.5 x 12-mm semicompliant balloon for the SB opening. The same steps were performed in a second model where a surgical clamp was placed in the main vessel to lower overall absolute values pressures. RESULTS: A strong correlation was found between JW and FW values (Pearson's coefficient, r=0.91). All wires could be safely retrieved. CONCLUSION: In bifurcation stenting, the Pd/Pa value of a second-generation optical pressure guidewire jailed in the SB is reliable compared with a FW inserted after stent implantation.

OBJECTIVES: It is unknown whether computed tomographic coronary angiography (CTCA) can be used to perform ultraselective invasive coronary angiography (ICA) by only visualizing the abnormal coronary artery on CTCA and defer visualization of the normal contralateral coronary artery. This study assessed the accuracy of CTCA in patients with coronary artery disease (CAD) on CTCA limited to either the left (LCA) or right coronary artery (RCA) in predicting a contralateral coronary artery without abnormalities on CTCA determined to be normal by ICA. METHODS: This retrospective analysis included patients with CAD limited to the LCA or RCA on CTCA. Primary endpoint was the accuracy of CTCA to predict a contralateral coronary artery without abnormalities on CTCA to be normal by ICA. Secondary endpoints were potential reductions in procedure time and radiation exposure if an ultraselective ICA approach would be used compared to standard ICA. RESULTS: In total, 202 patients were included. CTCA was correct in predicting a normal contralateral coronary artery in 201 of the 202 patients (99.5%). Deferring ICA of the normal contralateral coronary artery on CTCA resulted in a potential reduction in procedure time and dose area product of 4.22 ± 2.67 minutes (61 ± 16% reduction) and 1501 ± 1304 mGy•cm² (29 ± 13% reduction). CONCLUSIONS: In this retrospective study, CTCA was extremely accurate in predicting a normal contralateral coronary artery in patients with LCA- or RCA-limited CAD on CTCA. A potential CTCA-guided ultraselective ICA approach was feasible and would have led to a considerable decrease in procedure time and radiation exposure.

OBJECTIVES: Performing percutaneous coronary intervention (PCI) for fractional flow reserve (FFR) positive coronary lesions improves clinical outcomes and is recommended by international guidelines. It has been hypothesized that lesions with a positive FFR but a preserved coronary flow reserve (CFR) are less likely to be flow limiting and might best be treated medically. We investigated the association of CFR in FFR-positive lesions with clinical outcomes when treated medically, as well as the treatment effect of PCI vs medical therapy in FFR-positive lesions and a preserved CFR. METHODS: We performed a substudy of the randomized, multicenter Compare-Acute trial, in which stabilized ST-segment elevation myocardial infarction (STEMI) patients with non-culprit lesions were randomized to either FFR-guided PCI or medical therapy. Based on baseline and hyperemic pressure gradients, we computed physiologic limits of CFR, the so-called pressure-bounded CFR (pb-CFR), and classified lesions as low (

Background: \ud Pressure measurement for the duration of the wave-free period (WFP) is considered essential for resting-state physiological assessment of coronary stenosis severity using the instantaneous wave-free ratio (iFR).\ud \ud Objectives: \ud The aim of this study was to compare other diastolic resting indexes to iFR.\ud \ud Methods: \ud In the population of the VERIFY2 (Pd/Pa vs iFR in an Unselected Population Referred for Invasive Angiography) study, iFR calculated by proprietary software (Volcano Harvest, Volcano Corporation, Rancho Cordova, California) was compared with the ratio of resting distal coronary pressure and aortic pressure during the complete duration of diastole (dPR), 25% to 75% of diastole (dPR25–75), and midpoint of diastole (dPRmid), along with Matlab calculated iFR (iFRmatlab) and iFR-like indexes shortening the length of the WFP by 50 and 100 ms (iFR−50ms and iFR−100ms), respectively. Mutual differences, Spearman correlations, area under the curve values from receiver-operating characteristic analyses, and diagnostic performance with respect to iFR and fractional flow reserve (FFR) were calculated for all indexes.\ud \ud Results: \ud Median iFR in 197 patients with 257 vessels was 0.91 with an interquartile range of 0.87 to 0.95. The mutual differences (± SD) with iFR were 0.006 ± 0.011 (dPR), 0.001 ± 0.007 (dPR25–75), 0.001 ± 0.008 (dPRmid), 0.005 ± 0.009 (iFRmatlab), 0.003 ± 0.008 (iFR−50ms), and 0.001 ± 0.009 (iFR−100ms). Correlations for all indexes with iFR were >0.99 (p < 0.001 for all). Area under the curve values for predicting iFR were >0.99 for all indexes as well. Diagnostic accuracy compared with FFR was 76% to 77% for all indexes including iFR.\ud \ud Conclusions: \ud All diastolic resting indexes tested were identical to iFR, both numerically and with respect to their agreement with FFR. A numerically equal value to iFR can be determined without restriction to the WFP. Cutoff values, guidelines, and clinical recommendations for iFR can therefore be extended to these other indexes. (Pd/Pa vs iFR in an Unselected Population Referred for Invasive Angiography [VERIFY2]; NCT02377310).

Introduction The aim of this study was to compare magnetic resonance angiography (MRA) with digital subtraction angiography (DSA) in the preoperative assessment of crural arteries and their skin perforators prior to free fibular transfer. Patients and methods Fifteen consecutive patients, scheduled for free vascularized fibular flap transfer, were subjected to DSA as well as MRA of the crural arteries of both legs (n = 30). All DSA and MRA images were assessed randomly, blindly, and independently by two radiologists. Each of the assessors scored the degree of stenosis of various segments on a 5 point scale from 0 (occlusive) to 4 (no stenosis). The Cohen's Kappa coefficient was used to assess the agreement between DSA and MRA scores. In addition, the number of cutaneous perforators were scored and the assessors were asked if they would advise against fibula harvest and transplantation based on the images. Results A Cohen's Kappa of 0.64, indicating "substantial agreement of stenosis severity scores" was found between the two imaging techniques. The sensitivity of MRA to detect a stenosis compared with DSA was 79% (CI95%:60-91), and a specificity of 98% (CI95%: 97-99). In 53 out of 60 assessments, advice on suitability for transfer were equal between DSA and MRA. The median number of cutaneous perforators that perfuse the skin overlying the fibula per leg was one for DSA as well as MRA (P = 0.142).Conclusions A substantial agreement in the assessment of stenosis severity was found between DSA and MRA. The results suggest that MRA is a good alternative to DSA in the preoperative planning of free fibula flap transplantation. © 2013 Wiley Periodicals, Inc. Microsc. Res. Tech., 2013.

The Impella 2.5 left percutaneous (LP), a relatively new transvalvular assist device, challenges the position of the intra-aortic balloon pump (IABP), which has a long record in supporting patients after myocardial infarction and cardiac surgery. However, while more costly and more demanding in management, the advantages of the Impella 2.5 LP are yet to be established. The aim of this study was to evaluate the benefits of the 40 cc IABP and the Impella 2.5 LP operating at 47,000 rpm in vitro, and compare their circulatory support capabilities in terms of cardiac output, coronary flow, cardiac stroke work, and arterial blood pressure. Clinical scenarios of cardiogenic preshock and cardiogenic shock (CS), with blood pressure depression, lowered cardiac output, and constant heart rate of 80 bpm, were modeled in a model-controlled mock circulation, featuring a systemic, pulmonary, and coronary vascular bed. The ventricles, represented by servomotor-operated piston pumps, included the Frank-Starling mechanism. The systemic circulation was modeled with a flexible tube having close-to-human aortic dimensions and compliance properties. Proximally, it featured a branch mimicking the brachiocephalic arteries and a physiological correct coronary flow model. The rest of the systemic and pulmonary impedance was modeled by four-element Windkessel models. In this system, the enhancement of coronary flow and blood pressure was tested with both support systems under healthy and pathological conditions. Hemodynamic differences between the IABP and the Impella 2.5 LP were small. In our laboratory model, both systems approximately yielded a 10% cardiac output increase and a 10% coronary flow increase. However, since the Impella 2.5 LP provided significantly better left ventricular unloading, the circulatory support capabilities were slightly in favor of the Impella 2.5 LP. On the other hand, pulsatility was enhanced with the IABP and lowered with the Impella 2.5 LP. The support capabilities of both the IABP and the Impella 2.5 LP strongly depended on the simulated hemodynamic conditions. Maximum hemodynamic benefits were achieved when mechanical circulatory support was applied on a simulated scenario of deep CS.?