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Background: We evaluate the prognostic value of measuring fractional flow reserve (FFR) after percutaneous coronary intervention (post-PCI FFR) and intravascular imaging in patients undergoing PCI for 3-vessel coronary artery disease in the FAME 3 trial (Fractional Flow Reserve versus Angiography for Multivessel Evaluation). Methods: The FAME 3 trial is a multicenter, international, randomized study comparing FFR-guided PCI with coronary artery bypass grafting in patients with multivessel coronary artery disease. PCI was not noninferior with respect to the primary end point of death, myocardial infarction, stroke, or repeat revascularization at 1 year. Post-PCI FFR data were acquired on a patient and vessel-related basis. Intravascular imaging guidance was tracked. The primary end point is a comparison of target vessel failure (TVF) defined as a composite of cardiac death, target vessel myocardial infarction, and target vessel revascularization at 1 year based on post-PCI FFR values. Cox regression with robust SEs was used for analysis. Results: Of the 757 patients randomized to PCI, 461 (61%) had post-PCI FFR measurement and 11.1% had intravascular imaging performed. The median post-PCI FFR was 0.89 [IQR‚ 0.85–0.94]. On a vessel-level, post-PCI FFR was found to be a significant predictor of TVF univariately (hazard ratio=0.67 [95% CI‚ 0.48–0.93] for 0.1 unit increase, P =0.0165). On a patient-level, the single lowest post-PCI FFR value was also found to be a significant predictor of TVF univariately (hazard ratio=0.65 [95% CI‚ 0.48–0.89] for 0.1 unit increase, P =0.0074). Post-PCI FFR was an independent predictor of TVF in multivariable analysis adjusted for key clinical parameters. Outcomes were similar between patients who had intravascular imaging guidance and those who did not. Conclusions: Post-PCI FFR measurement was a significant predictor of TVF on a vessel and patient level and an independent predictor of outcomes in a population with complex 3-vessel coronary artery disease eligible for coronary artery bypass grafting. The limited use of intravascular imaging did not affect outcomes. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02100722. [ABSTRACT FROM AUTHOR]

Background--Recent data suggest that circulating biomarkers may predict outcome in patients undergoing transcatheter aortic valve replacement (TAVR). We examined the association between inflammatory, myocardial, and renal biomarkers and their role in ventricular recovery and outcome after TAVR. Methods and Results--A total of 112 subjects undergoing TAVR were included in the prospective registry. Plasma levels of B-type natriuretic peptide, hs-TnI (high-sensitivity troponin I), CRP (C-reactive protein), GDF-15 (growth differentiation factor 15), GAL-3 (galectin-3), and Cys-C (cystatin-C) were assessed before TAVR and in 100 sex-matched healthy controls. Among echocardiographic parameters, we measured global longitudinal strain, indexed left ventricular mass, and indexed left atrial volume. The TAVR group included 59% male, with an average age of 84 years, and 1-year mortality of 18%. Among biomarkers, we found GDF-15 and CRP to be strongly associated with all-cause mortality (P<0.001). Inclusion of GDF-15 and CRP to the Society of Thoracic Surgeons score significantly improved C index (0.65-0.79; P<0.05) and provided a category-free net reclassification improvement of 106% at 2 years (P=0.01). Among survivors, functional recovery in global longitudinal strain (>15% improvement) and indexed left ventricular mass (>20% decrease) at 1 year occurred in 48% and 22%, respectively. On multivariate logistic regression, lower baseline GDF-15 was associated with improved global longitudinal strain at 1 year (hazard ratio=0.29; P<0.001). Furthermore, improvement in global longitudinal strain at 1 month correlated with lower overall mortality (hazard ratio=0.45; P=0.03). Conclusions--Elevated GDF-15 correlates with lack of reverse remodeling and increased mortality after TAVR and improves risk prediction of mortality when added to the Society of Thoracic Surgeons score. [ABSTRACT FROM AUTHOR]

Background—Although significant undersizing often results in incomplete stent apposition or underexpansion, the possible impact of oversized stent implantation on arterial wall injury has not been systematically investigated with drug-eluting stents. The aim of this study was to investigate the impact of stent oversizing on acute and long-term outcomes after drugeluting stents implantation in de novo coronary lesions. Methods and Results—Serial (baseline and 6–12 months) coronary angiography and intravascular ultrasound were performed in 2931 lesions treated with drug-eluting stents (355 sirolimus, 846 paclitaxel, 1387 zotarolimus, and 343 everolimus). The percentage of stent oversizing to angiographic reference vessel diameter (RVD) was calculated as (nominal stent diameter–RVD)/RVD×100 (%). Clinical outcomes, including target lesion revascularization and stent thrombosis, were followed for 1 year. Overall, smaller preintervention RVD was associated with higher percentage of stent oversizing (P<0.001). The significant oversizing group underwent less post-dilatation (P=0.002) but achieved greater stent expansion (P<0.001) and less incomplete stent apposition (P<0.001) without increase of edge dissection after procedure. When stratified by vessel size and stent oversizing, progressive decreases of restenosis (P=0.002) and target lesion revascularization rates (P=0.007) were found in favor of larger vessel size and oversized stents. Stent thrombosis was observed the most in small RVD with low percentage of stent oversizing group among the subgroups (P=0.040). Conclusions—The positive impact of stent oversizing was documented on procedural and clinical outcomes. In particular, small vessels treated with smaller stents were associated with greater adverse events, suggesting that aggressive selection of larger stents, with appropriate attention to edge effects, may optimize long-term outcomes, even in drug-eluting stents implantation. [ABSTRACT FROM AUTHOR]

The article discusses the paper "Dual Manganese-Enhanced and Delayed Gadolinium-Enhanced MRI Detects Myocardial Border Zone Injury in a Pig Ischemia-Reperfusion Model," by Rajesh Dash and others. It states that the study was conducted to determine if dual-contrast myocardial assessment on a pig combining delayed-enhancement magnetic resonance imaging (DEMRI) and manganese enhanced MRI (MEMRI) can detect viable infarct border zone (BZ) myocardium in vivo. The method and results, follow.

Supplemental Digital Content is available in the text. Background: Intracoronary acetylcholine (Ach) provocation testing is the gold standard for assessing coronary endothelial function. However, dosing regimens of Ach are quite varied in the literature, and there are limited data evaluating the optimal dose. We evaluated the dose-response relationship between Ach and minimal lumen diameter (MLD) by sex and studied whether incremental intracoronary Ach doses given during endothelial function testing improve its diagnostic utility. Methods: We evaluated 65 men and 212 women with angina and no obstructive coronary artery disease who underwent endothelial function testing using the highest tolerable dose of intracoronary Ach, up to 200 μg. Epicardial endothelial dysfunction was defined as a decrease in MLD >20% after intracoronary Ach by quantitative coronary angiography. We used a linear mixed effects model to evaluate the dose-response relationship. Deming regression analysis was done to compare the %MLD constriction after incremental doses of intracoronary Ach. Results: The mean age was 53.5 years. Endothelial dysfunction was present in 186 (68.1%). Among men with endothelial dysfunction, there was a significant decrease in MLD/10 µg of Ach at doses above 50 μg and 100 µg, while this decrease in MLD was not observed in women (P <0.001). The %MLD constriction at 20 μg versus 50 μg and 50 μg versus 100 μg were not equivalent while the %MLD constriction at 100 μg versus 200 μg were equivalent. Conclusions: Women and men appear to have different responses to Ach during endothelial function testing. In addition to having a greater response to intracoronary Ach at all doses, men also demonstrate an Ach-MLD dose-response relationship with doses up to 200 μg, while women have minimal change in MLD with doses above 50 µg. An incremental dosing regimen during endothelial function testing appears to improve the diagnostic utility of the test and should be adjusted based on the sex of the patient. [ABSTRACT FROM AUTHOR]

Background: The clinical impact of a chronic total occlusion (CTO) in patients with 3-vessel coronary artery disease undergoing fractional flow reserve-guided percutaneous coronary intervention (PCI) with current-generation drug-eluting stents or coronary artery bypass grafting (CABG) is unclear., Methods: The FAME 3 trial (Fractional Flow Reserve Versus Angiography for Multivessel Evaluation 3) compared fractional flow reserve-guided PCI with CABG in patients with 3-vessel coronary artery disease. The primary end point was major adverse cardiac and cerebrovascular events, a composite of death, myocardial infarction, stroke, or repeat revascularization at 1 year. In this substudy, the 3-year outcomes were analyzed in patients with or without a CTO., Results: Of the patients randomized to PCI or CABG in the FAME 3 trial, 305 (21%) had a CTO. In the PCI arm, revascularization of the CTO was attempted in 61% with a procedural success rate of 88%. The incidence of major adverse cardiac and cerebrovascular events at 3 years was not significantly different between those with or without a CTO in both the PCI (15.2% versus 20.1%; adjusted hazard ratio, 0.62 [95% CI, 0.38-1.03]; P =0.07) and the CABG (13.0% versus 12.9%; adjusted hazard ratio, 0.96 [95% CI, 0.55-1.66]; P =0.88) arms. In those without a CTO, PCI was associated with a significantly higher risk of major adverse cardiac and cerebrovascular events compared with CABG (adjusted hazard ratio, 1.61 [95% CI, 1.20-2.17]; P <0.01) but not in those with a CTO (adjusted hazard ratio, 1.21 [95% CI, 0.64-2.28]; P =0.56; P interaction =0.31)., Conclusions: The presence of a CTO did not significantly impact the treatment effect of PCI versus CABG at 3 years in patients with 3-vessel coronary artery disease., Clinical Trial Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02100722., Competing Interests: Dr Otsuki has received research grants from the Uehara Memorial Foundation, Abbott, Medtronic, Boston Scientific, and Terumo. Dr Fearon has received institutional research grants from Abbott Vascular and Medtronic, had a consulting relationship with CathWorks, and has stock options with HeartFlow. Dr Mavromatis reported that his institution (Atlanta Research Education Foundation) has received grant support from Stanford University. The other authors report no conflicts.

Background: Previous studies comparing percutaneous coronary intervention (PCI) with coronary artery bypass grafting (CABG) in patients with multivessel coronary disease not involving the left main have shown significantly lower rates of death, myocardial infarction (MI), or stroke after CABG. These studies did not routinely use current-generation drug-eluting stents or fractional flow reserve (FFR) to guide PCI., Methods: FAME 3 (Fractional Flow Reserve versus Angiography for Multivessel Evaluation) is an investigator-initiated, multicenter, international, randomized trial involving patients with 3-vessel coronary artery disease (not involving the left main coronary artery) in 48 centers worldwide. Patients were randomly assigned to receive FFR-guided PCI using zotarolimus drug-eluting stents or CABG. The prespecified key secondary end point of the trial reported here is the 3-year incidence of the composite of death, MI, or stroke., Results: A total of 1500 patients were randomized to FFR-guided PCI or CABG. Follow-up was achieved in >96% of patients in both groups. There was no difference in the incidence of the composite of death, MI, or stroke after FFR-guided PCI compared with CABG (12.0% versus 9.2%; hazard ratio [HR], 1.3 [95% CI, 0.98-1.83]; P =0.07). The rates of death (4.1% versus 3.9%; HR, 1.0 [95% CI, 0.6-1.7]; P =0.88) and stroke (1.6% versus 2.0%; HR, 0.8 [95% CI, 0.4-1.7]; P =0.56) were not different. MI occurred more frequently after PCI (7.0% versus 4.2%; HR, 1.7 [95% CI, 1.1-2.7]; P =0.02)., Conclusions: At 3-year follow-up, there was no difference in the incidence of the composite of death, MI, or stroke after FFR-guided PCI with current-generation drug-eluting stents compared with CABG. There was a higher incidence of MI after PCI compared with CABG, with no difference in death or stroke. These results provide contemporary data to allow improved shared decision-making between physicians and patients with 3-vessel coronary artery disease., Registration: URL: https://www., Clinicaltrials: gov; Unique identifier: NCT02100722., Competing Interests: Disclosures Dr Pijls receives research funding from Abbott, has consulting relationships with Abbott and Opsens, and has stock or stock options with ASML, General Electric, HeartFlow, Hexacath, and Philips. Dr Mansour has consulting relationships with Abbott Vascular, Amgen, AstraZeneca, Bayer, Boehringer Ingelheim, Novartis, Pfizer, and Servier Affaires, and received a research grant from Opsens Inc and Abbott Vascular. Dr Kala has a consulting relationship with Boston Scientific, Medtronic, and Servier Affaires, and receives honoraria from AstraZeneca and Bayer. Dr Angeras receives research funding from Abbott Vascular and AstraZeneca and has a consulting relationship with Abbott Vascular and Boston Scientific. Dr Miner has a consulting relationship with Abbott, Amgen, Astra Zeneca, Bayer, Boehringer, Novartis, Opsens, Pfizer, and Servier Affaires Medicales. Dr Engstrøm has a consulting relationship with Abbott Vascular, Bayer, and Novo Nordisk. Dr Christiansen has a consulting relationship with Abbott Vascular and has received research grants from Abbott Vascular. Dr Tonino has received research grants from Biosensors and Opsens. Dr Reardon has a consulting relationship with Boston Scientific and W.L. Gore & Associates. Dr Otsuki has received research grants from the Uehara Memorial Foundation, Abbott, Medtronic, Boston Scientific, and Terumo. Dr Kobayashi has a consulting relationship with Abbott Vascular. Dr Hlatky has a consulting relationship with Blue Cross and Blue Shield and research support from HeartFlow. Dr Mahaffey has received research grants or contracts from the American Heart Association, Apple, Inc, Bayer, California Institute Regenerative Medicine, Eidos, Ferring, Gilead, Google (Verily), Idorsia, Johnson & Johnson, Luitpold, PAC-12, Precordior, and Sanifit; has provided consulting or other services for Amgen, Applied Therapeutics, AstraZeneca, Bayer, CSL Behring, Elsevier, FibroGen, Inova, Johnson & Johnson, Lexicon, MyoKardia, Novartis, Novo Nordisk, Otsuka, PhaseBio, Portola, Quidel, Sanofi, and Theravance; and has equity in Precordior. Dr Yeung has a consulting relationship with Medtronic. Dr De Bruyne has an institutional consulting relationship with Boston Scientific, Abbott Vascular, CathWorks, Siemens, GE Healthcare, and Coroventis Research; receives institutional research grants from Abbott Vascular, Coroventis Research, CathWorks, and Boston Scientific; and holds minor equities in Philips, Siemens, GE Healthcare, CathWorks, Edwards Life Sciences, HeartFlow, Opsens, Celyad, Xenter, Medyria, Bayer, and Sanofi. Dr Fearon receives research funding from Abbott, Medtronic, and Boston Scientific and has a consulting relationship with Siemens and CathWorks and stock options with HeartFlow. The other authors report no conflicts of interest.

Background: Recent data suggest that circulating biomarkers may predict outcome in patients undergoing transcatheter aortic valve replacement (TAVR). We examined the association between inflammatory, myocardial, and renal biomarkers and their role in ventricular recovery and outcome after TAVR., Methods and Results: A total of 112 subjects undergoing TAVR were included in the prospective registry. Plasma levels of B-type natriuretic peptide, hs-TnI (high-sensitivity troponin I), CRP (C-reactive protein), GDF-15 (growth differentiation factor 15), GAL-3 (galectin-3), and Cys-C (cystatin-C) were assessed before TAVR and in 100 sex-matched healthy controls. Among echocardiographic parameters, we measured global longitudinal strain, indexed left ventricular mass, and indexed left atrial volume. The TAVR group included 59% male, with an average age of 84 years, and 1-year mortality of 18%. Among biomarkers, we found GDF-15 and CRP to be strongly associated with all-cause mortality ( P <0.001). Inclusion of GDF-15 and CRP to the Society of Thoracic Surgeons score significantly improved C index (0.65-0.79; P <0.05) and provided a category-free net reclassification improvement of 106% at 2 years ( P =0.01). Among survivors, functional recovery in global longitudinal strain (>15% improvement) and indexed left ventricular mass (>20% decrease) at 1 year occurred in 48% and 22%, respectively. On multivariate logistic regression, lower baseline GDF-15 was associated with improved global longitudinal strain at 1 year (hazard ratio=0.29; P <0.001). Furthermore, improvement in global longitudinal strain at 1 month correlated with lower overall mortality (hazard ratio=0.45; P =0.03)., Conclusions: Elevated GDF-15 correlates with lack of reverse remodeling and increased mortality after TAVR and improves risk prediction of mortality when added to the Society of Thoracic Surgeons score., (© 2017 American Heart Association, Inc.)

Background: Although significant undersizing often results in incomplete stent apposition or underexpansion, the possible impact of oversized stent implantation on arterial wall injury has not been systematically investigated with drug-eluting stents. The aim of this study was to investigate the impact of stent oversizing on acute and long-term outcomes after drug-eluting stents implantation in de novo coronary lesions., Methods and Results: Serial (baseline and 6-12 months) coronary angiography and intravascular ultrasound were performed in 2931 lesions treated with drug-eluting stents (355 sirolimus, 846 paclitaxel, 1387 zotarolimus, and 343 everolimus). The percentage of stent oversizing to angiographic reference vessel diameter (RVD) was calculated as (nominal stent diameter-RVD)/RVD×100 (%). Clinical outcomes, including target lesion revascularization and stent thrombosis, were followed for 1 year. Overall, smaller preintervention RVD was associated with higher percentage of stent oversizing ( P <0.001). The significant oversizing group underwent less post-dilatation ( P =0.002) but achieved greater stent expansion ( P <0.001) and less incomplete stent apposition ( P <0.001) without increase of edge dissection after procedure. When stratified by vessel size and stent oversizing, progressive decreases of restenosis ( P =0.002) and target lesion revascularization rates ( P =0.007) were found in favor of larger vessel size and oversized stents. Stent thrombosis was observed the most in small RVD with low percentage of stent oversizing group among the subgroups ( P =0.040)., Conclusions: The positive impact of stent oversizing was documented on procedural and clinical outcomes. In particular, small vessels treated with smaller stents were associated with greater adverse events, suggesting that aggressive selection of larger stents, with appropriate attention to edge effects, may optimize long-term outcomes, even in drug-eluting stents implantation., (© 2017 American Heart Association, Inc.)

Background: The aim of this study is to determine the prognostic value of invasively assessing coronary physiology early after heart transplantation., Methods and Results: Seventy-four cardiac transplant recipients had fractional flow reserve, coronary flow reserve, index of microcirculatory resistance (IMR), and intravascular ultrasound performed down the left anterior descending coronary artery soon after (baseline) and 1 year after heart transplantation. The primary end point was the cumulative survival free of death or retransplantation at a mean follow-up of 4.5±3.5 years. The cumulative event-free survival was significantly lower in patients with a fractional flow reserve <0.90 at baseline (42% versus 79%; P=0.01) or an IMR ≥20 measured 1 year after heart transplantation (39% versus 69%; P=0.03). Patients in whom IMR decreased or did not change from baseline to 1 year had higher event-free survival compared with patients with an increase in IMR (66% versus 36%; P=0.03). Fractional flow reserve <0.90 at baseline (hazard ratio, 0.13; 95% confidence interval, 0.02-0.81; P=0.03), IMR ≥20 at 1 year (hazard ratio, 3.93; 95% confidence interval, 1.08-14.27; P=0.04), and rejection during the first year (hazard ratio, 6.00; 95% confidence interval, 1.56-23.09; P=0.009) were independent predictors of death/retransplantation, whereas intravascular ultrasound parameters were not., Conclusions: Invasive measures of coronary physiology (fractional flow reserve and IMR) determined early after heart transplantation are significant predictors of late death or retransplantation., (© 2016 American Heart Association, Inc.)

Background: More than 20% of patients presenting to the cardiac catheterization laboratory with angina have no angiographic evidence of coronary artery disease. Despite a "normal" angiogram, these patients often have persistent symptoms, recurrent hospitalizations, a poor functional status, and adverse cardiovascular outcomes, without a clear diagnosis., Methods and Results: In 139 patients with angina in the absence of obstructive coronary artery disease (no diameter stenosis >50%), endothelial function was assessed; the index of microcirculatory resistance, coronary flow reserve, and fractional flow reserve were measured; and intravascular ultrasound was performed. There were no complications. The average age was 54.0±11.4 years, and 107 (77%) were women. All patients had at least some evidence of atherosclerosis based on an intravascular ultrasound examination of the left anterior descending artery. Endothelial dysfunction (a decrease in luminal diameter of >20% after intracoronary acetylcholine) was present in 61 patients (44%). Microvascular impairment (an index of microcirculatory resistance ≥25) was present in 29 patients (21%). Seven patients (5%) had a fractional flow reserve ≤0.80. A myocardial bridge was present in 70 patients (58%). Overall, only 32 patients (23%) had no coronary explanation for their angina, with normal endothelial function, normal coronary physiological assessment, and no myocardial bridging., Conclusions: The majority of patients with angina in the absence of obstructive coronary artery disease have occult coronary abnormalities. A comprehensive invasive assessment of these patients at the time of coronary angiography can be performed safely and provides important diagnostic information that may affect treatment and outcomes., (© 2015 American Heart Association, Inc.)

Background: We tested the hypothesis that multimodality imaging of mouse embryonic stem cells (mESCs) provides accurate assessment of cellular location, viability, and restorative potential after transplantation into different zones of myocardial infarction., Methods and Results: Mice underwent left anterior descending artery ligation followed by transplantation of dual-labeled mESCs with superparamagnetic iron oxide and luciferase via direct injection into 3 different zones of myocardial infarction: intra-infarction, peri-infarction, and normal (remote). One day after transplantation, magnetic resonance imaging enabled assessment of the precise anatomic locations of mESCs. Bioluminescence imaging allowed longitudinal analysis of cell viability through detection of luciferase activity. Subsequent evaluation of myocardial regeneration and functional restoration was performed by echocardiography and pressure-volume loop analysis. Using 16-segment analysis, we demonstrated precise localization of dual-labeled mESCs. A strong correlation between histology and magnetic resonance imaging was established (r=0.962, P=0.002). Bioluminescent imaging data demonstrated that cell viability in the remote group was significantly higher than in other groups. Echocardiography and pressure-volume loop analysis revealed improved functional restoration in animals treated with mESCs, although myocardial regeneration was not observed., Conclusions: Multimodality evaluation of mESC engraftment in the heterogeneous tissue of myocardial infarction is possible. Magnetic resonance imaging demonstrated accurate anatomic localization of dual-labeled mESCs. Bioluminescent imaging enabled assessment of variable viability of mESCs transplanted into the infarcted myocardium. Echocardiography and pressure-volume loop analysis validated the restorative potential of mESCs. Although mESCs transplanted into the remote zone demonstrated the highest viability, precise delivery of mESCs into the peri-infarction region might be equally critical in restoring the injured myocardium.

Background: A simple, reproducible invasive method for assessing the coronary microcirculation is lacking. A novel index of microcirculatory resistance (IMR) has been shown in animals to correlate with true microvascular resistance and, unlike coronary flow reserve (CFR), to be independent of the epicardial artery. We sought to compare the reproducibility and hemodynamic dependence of IMR with CFR in humans., Methods and Results: Using a pressure-temperature sensor-tipped coronary wire, thermodilution-derived CFR and IMR were measured, along with fractional flow reserve (FFR), in 15 coronary arteries (15 patients) under the following hemodynamic conditions: (1) twice at baseline; (2) during right ventricular pacing at 110 bpm; (3) during intravenous infusion of nitroprusside; and (4) during intravenous dobutamine infusion. Mean CFR did not change during baseline measurements or during nitroprusside infusion but decreased during pacing (from 3.1+/-1.1 at baseline to 2.3+/-1.2 during pacing, P<0.05) and during dobutamine infusion (from 3.0+/-1.0 to 1.7+/-0.6 with dobutamine, P<0.0001). By comparison, mean values for IMR and FFR remained similar throughout all hemodynamic conditions. The mean coefficient of variation between 2 baseline measurements was significantly lower for IMR (6.9+/-6.5%) and FFR (1.6+/-1.6%) than for CFR (18.6+/-9.6%; P<0.01). Mean correlation between baseline measurements and each hemodynamic intervention was superior for IMR (r=0.90+/-0.05) and FFR (r=0.86+/-0.12) compared with CFR (r=0.70+/-0.05; P<0.05)., Conclusions: Compared with CFR, IMR provides a more reproducible assessment of the microcirculation, which is independent of hemodynamic perturbations. Simultaneous measurement of FFR and IMR may provide a comprehensive and specific assessment of coronary physiology at both epicardial and microvascular levels, respectively.

Background: Several clinical studies are evaluating the therapeutic potential of delivery of various progenitor cells for treatment of injured hearts. However, the actual fate of delivered cells has not been thoroughly assessed for any cell type. We evaluated the short-term fate of peripheral blood mononuclear cells (PBMNCs) after intramyocardial (IM), intracoronary (IC), and interstitial retrograde coronary venous (IRV) delivery in an ischemic swine model., Methods and Results: Myocardial ischemia was created by 45 minutes of balloon occlusion of the left anterior descending coronary artery. Six days later, 10(7) 111indium-oxine-labeled human PBMNCs were delivered by IC (n=5), IM (n=6), or IRV (n=5) injection. The distribution of injected cells was assessed by gamma-emission counting of harvested organs. For each delivery method, a significant fraction of delivered cells exited the heart into the pulmonary circulation, with 26+/-3% (IM), 47+/-1% (IC), and 43+/-3% (IRV) of cells found localized in the lungs. Within the myocardium, significantly more cells were retained after IM injection (11+/-3%) compared with IC (2.6+/-0.3%) (P<0.05) delivery. IRV delivery efficiency (3.2+/-1%) trended lower than IM infusion for PBMNCs, but this difference did not reach significance. The IM technique displayed the greatest variability in delivery efficiency by comparison with the other techniques., Conclusions: The majority of delivered cells is not retained in the heart for each delivery modality. The clinical implications of these findings are potentially significant, because cells with proangiogenic or other therapeutic effects could conceivably have effects in other organs to which they are not primarily targeted but to which they are distributed. Also, we found that although IM injection was more efficient, it was less consistent in the delivery of PBMNCs compared with IC and IRV techniques.

Background: The effect of epicardial artery stenosis on myocardial microvascular resistance remains controversial. Recruitable collateral flow, which may affect resistance, was not incorporated into previous measurements., Methods and Results: In an open-chest pig model, distal coronary pressure was measured with a pressure wire, and the apparent minimal microvascular resistance was calculated during peak hyperemia as pressure divided by flow, measured either with a flow probe around the coronary artery (R(micro app)) or with a novel thermodilution technique (apparent index of microcirculatory resistance [IMR(app)]). These apparent resistances were compared with the actual R(micro) and IMR after the coronary wedge pressure and collateral flow were incorporated into the calculation. Measurements were made at baseline (no stenosis) and after creation of moderate and severe epicardial artery stenoses. In 6 pigs, 189 measurements of R(micro) and IMR were made under the various epicardial artery conditions. Without consideration of collateral flow, R(micro app) (0.43+/-0.12 to 0.46+/-0.10 to 0.51+/-0.11 mm Hg/mL per minute) and IMR(app) (14+/-4 to 17+/-7 to 20+/-10 U) increased progressively and significantly with increasing epicardial artery stenosis (P<0.001 for both). With the incorporation of collateral flow, neither R(micro) nor IMR increased as a result of increasing epicardial artery stenosis., Conclusions: After collateral flow is taken into account, the minimum achievable microvascular resistance is not affected by increasing epicardial artery stenosis.

Background: Thermodilution coronary flow reserve (CFRthermo) is a new technique for invasively measuring coronary flow reserve (CFR) with a coronary pressure wire and is based on the ability of the pressure transducer to also measure temperature changes. Whether CFRthermo correlates well enough with absolute flow-derived CFR (CFRflow) to replace Doppler wire-derived CFR (CFRDoppler) remains unclear., Methods and Results: In an open-chest pig model, CFRthermo was measured in the left anterior descending (LAD) artery and compared with CFRDoppler and CFRflow, measured with an external flow probe placed around the LAD. In 9 pigs, CFR was measured simultaneously by all 3 means in the normal LAD and after creation of an epicardial LAD stenosis. To determine the added effect of microvascular disease, measurements of flow reserve were also performed after disruption of the coronary microcirculation with embolized microspheres. Intracoronary papaverine (20 mg) was used to induce hyperemia. In a total of 61 paired measurements, CFRthermo correlated strongly with the reference standard CFRflow (r=0.85, P<0.001). CFRDoppler correlated less well with CFRflow (r=0.72, P<0.001). Bland-Altman analysis showed a closer agreement between CFRthermo and CFRflow., Conclusions: CFRthermo correlates better with CFRflow than does CFRDoppler.

Background: The utility of measuring fractional flow reserve (FFR) to assess cardiac transplant arteriopathy has not been evaluated. Measuring coronary flow reserve (CFR) as well as FFR could add information about the microcirculation, but until recently, this has required two coronary wires. We evaluated a new method for simultaneously measuring FFR and CFR with a single wire to investigate transplant arteriopathy., Methods and Results: In 53 cases of asymptomatic cardiac transplant recipients without angiographically significant coronary disease, FFR and thermodilution-derived CFR (CFRthermo) were measured simultaneously with the same coronary pressure wire in the left anterior descending artery and compared with volumetric intravascular ultrasound (IVUS) imaging. The average FFR was 0.88+/-0.07; in 75% of cases, the FFR was less than the normal threshold of 0.94; and in 15% of cases, the FFR was < or =0.80, the upper boundary of the gray zone of the ischemic threshold. There was a significant inverse correlation between FFR and IVUS-derived measures of plaque burden, including percent plaque volume (r=0.55, P<0.0001). The average CFRthermo was 2.5+/-1.2; in 47% of cases, CFRthermo was < or =2.0. In 14%, the FFR was normal (> or =0.94) and the CFR was abnormal (<2.0), suggesting predominant microcirculatory dysfunction., Conclusions: FFR correlates with IVUS findings and is abnormal in a significant proportion of asymptomatic cardiac transplant patients with normal angiograms. Simultaneous measurement of CFR with the same pressure wire, with the use of a novel coronary thermodilution technique, is feasible and adds information to the physiological evaluation of these patients.

Background: Motexafin lutetium (MLu; Antrin) is a photosensitizer that is taken up by atherosclerotic plaque and concentrated within macrophages and vascular smooth muscle cells. After photoactivation with far red light, MLu facilitates production of cytotoxic oxygen radicals that mediate apoptosis. We assessed the safety and tolerability of phototherapy (PT) with MLu in patients undergoing percutaneous coronary intervention with stent deployment., Methods and Results: An open-label, phase I, drug and light dose-escalation clinical trial of MLu PT enrolled 80 patients undergoing de novo coronary stent deployment. MLu was administered to 79 patients by intravenous infusion 18 to 24 hours before procedure, and photoactivation was performed after balloon predilatation and before stent deployment. Clinical evaluation, serial quantitative angiography, and intravascular ultrasound were performed periprocedurally and at 6 months follow-up. MLu PT was well tolerated without serious dose-limiting toxicities, and side effects (paresthesia and rash) were minor. No adverse angiographic outcomes were attributed to phototherapy., Conclusions: This study demonstrates that coronary MLu PT seems safe, and the maximum well-tolerated MLu dose and range of tolerated light doses were identified. These data can be used in phase II efficacy trials of MLu PT for the treatment of coronary atherosclerosis or vulnerable plaque.