Equipment utilization in chronic total occlusion percutaneous coronary interventions: Insights from the PROGRESS-CTO registry.

BACKGROUND: We examined guidewire and microcatheter utilization during chronic total occlusion (CTO) percutaneous coronary intervention (PCI). METHODS: We examined device utilization in 2,968 CTO PCIs performed in 2,936 patients at 19 US and two international center between January 2016 and January 2019. RESULTS: The median number of antegrade guidewires used per case declined (5 in 2016 vs 3 in 2019) and was higher in higher complexity lesions (2 in J-CTO 0 vs. 8 in J-CTO 4 or 5 score). In antegrade-only procedures, the most frequently used guidewires were the Pilot 200 (Abbott Vascular, 37%), Fielder XT (Asahi Intecc, 25%) and Gaia third (Asahi Intecc, 18%), while the most commonly used microcatheters were the Turnpike Spiral (Vascular Solutions, 18%) and Turnpike (Vascular Solutions, 16%). Compared with 2012-2015, during 2016-2019 use of novel equipment such as the Gaia guidewires and the Turnpike microcatheters led to decreased use of Confianza Pro 12 (Asahi Intecc) wire and Corsair (Asahi Intecc) family of microcatheters. In retrograde cases, the guidewires most commonly used were the Sion (44%), Pilot 200 (27%) and Fielder FC (26%), while the Corsair/Corsair Pro, Turnpike LP (Vascular Solutions) and Caravel (Asahi Intecc) were the most frequently used microcatheters for collateral crossing (29%, 26% and 22%, respectively). CONCLUSIONS: The most commonly used guidewires during CTO PCI are polymer-jacketed guidewires and the most commonly used microcatheters are torquable microcatheters.

Outcomes of subintimal plaque modification in chronic total occlusion percutaneous coronary intervention.

BACKGROUND: When crossing into the distal true lumen fails during chronic total occlusion (CTO) percutaneous coronary intervention (PCI), subintimal plaque modification (SPM) is often performed to restore antegrade flow and facilitate subsequent lesion recanalization. METHODS: Between January 2012 and May 4, 2019, 4,659 CTO PCIs were included in the PROGRESS-CTO registry, of which 935 (20%) had a prior unsuccessful attempt. Of those 935 patients, 119 (13%) had prior SPM. We analyzed the outcomes of the 58 SPM procedures for which data were available, as well as the outcomes of the 60 subsequent CTO PCI attempts. RESULTS: Mean patient age was 67 ± 9 years and 86% were men. Patients had high prevalence of cardiovascular risk factors such as dyslipidemia (91%), hypertension (93%) diabetes (48%), prior PCI (61%), and prior coronary artery bypass graft surgery (47%). The target CTO lesions often had proximal cap ambiguity (54%), moderate/severe calcification (73%), moderate/severe tortuosity (63%), and high J-CTO score (mean 3.2 ± 1.1). The technical and procedural success of subsequent CTO PCI were high (83% for both) with an acceptable rate of in-hospital major adverse cardiovascular events (3.3%). Technical and procedural success were higher for repeat attempts that were performed ≥60 days after the index CTO PCI (94% vs. 69%, p = .015). Median (interquartile range) subsequent procedure time was 147 (100, 215) min, contrast volume was 185 (150, 260) ml, and air kerma radiation dose was 2.5 (1.4, 4.2) Gray. CONCLUSION: Repeat CTO PCI attempts after SPM are associated with high likelihood for successful revascularization with acceptable risks.

Long-Term Association of Low-Density Lipoprotein Cholesterol With Cardiovascular Mortality in Individuals at Low 10-Year Risk of Atherosclerotic Cardiovascular Disease.

BACKGROUND: The associations of low-density lipoprotein cholesterol (LDL-C) with cardiovascular disease (CVD) and coronary heart disease mortality in an exclusively low estimated 10-year risk group are not well delineated. We sought to determine the long-term associations of various LDL-C and non-high-density lipoprotein cholesterol (HDL-C) thresholds and CVD and coronary heart disease mortality in a large, low 10-year risk cohort. METHODS: The study sample included participants of the CCLS (Cooper Center Longitudinal Study) without a history of CVD or diabetes mellitus and defined as low risk (<7.5%) for 10-year atherosclerotic CVD events at baseline based on Pooled Cohort Risk Assessment Equations. The associations of fasting LDL-C and non-HDL-C with CVD mortality were tested with Cox proportional hazards models. RESULTS: In 36 375 participants (72% men, median age 42) followed for a median of 26.8 years, 1086 CVD and 598 coronary heart disease deaths occurred. Compared with LDL-C <100 mg/dL, LDL-C categories 100 to 129 mg/dL, 130 to 159 mg/dL, 160 to 189.9 mg/dL, and ≥190 mg/dL were associated with a significantly higher risk of CVD death, with hazard ratios of 1.4 (95% CI, 1.1-1.7), 1.3 (95% CI, 1.1-1.6), 1.9 (95% CI, 1.5-2.4), and 1.7 (95% CI, 1.3-2.3), and mean reductions in years free of CVD death of 1.8, 1.1, 4.3, and 3.9, respectively. After adjustment for atherosclerotic CVD risk factors, LDL-C categories 160 to 189 mg/dL and ≥190 mg/dL remained independently associated with CVD mortality, with hazard ratios of 1.7 (95% CI, 1.4-2.2) and 1.5 (95% CI, 1.2-2.1), respectively. In multivariable-adjusted models using non-HDL-C <130 mg/dL as the reference, non-HDL-C 160 to 189 mg/dL, 190 to 219 mg/dL, and ≥220 mg/dL were significantly associated with CVD death, with hazard ratios of 1.3 (95% CI, 1.1-1.6), 1.8 (95% CI, 1.4-2.2), and 1.5 (95% CI, 1.2-2.0), respectively. Restricting the cohort to those with 10-year risk <5% did not diminish the associations of LDL-C and non-HDL-C with CVD mortality. CONCLUSIONS: In a low 10-year risk cohort with long-term follow-up, LDL-C and non-HDL-C ≥160 mg/dL were independently associated with a 50% to 80% increased relative risk of CVD mortality. These findings may have implications for future cholesterol treatment paradigms.

Effect of Omega-3 Acid Ethyl Esters on Left Ventricular Remodeling After Acute Myocardial Infarction: The OMEGA-REMODEL Randomized Clinical Trial.

BACKGROUND: Omega-3 fatty acids from fish oil have been associated with beneficial cardiovascular effects, but their role in modifying cardiac structures and tissue characteristics in patients who have had an acute myocardial infarction while receiving current guideline-based therapy remains unknown. METHODS: In a multicenter, double-blind, placebo-controlled trial, participants presenting with an acute myocardial infarction were randomly assigned 1:1 to 6 months of high-dose omega-3 fatty acids (n=180) or placebo (n=178). Cardiac magnetic resonance imaging was used to assess cardiac structure and tissue characteristics at baseline and after study therapy. The primary study endpoint was change in left ventricular systolic volume index. Secondary endpoints included change in noninfarct myocardial fibrosis, left ventricular ejection fraction, and infarct size. RESULTS: By intention-to-treat analysis, patients randomly assigned to omega-3 fatty acids experienced a significant reduction of left ventricular systolic volume index (-5.8%, P=0.017), and noninfarct myocardial fibrosis (-5.6%, P=0.026) in comparison with placebo. Per-protocol analysis revealed that those patients who achieved the highest quartile increase in red blood cell omega-3 index experienced a 13% reduction in left ventricular systolic volume index in comparison with the lowest quartile. In addition, patients in the omega-3 fatty acid arm underwent significant reductions in serum biomarkers of systemic and vascular inflammation and myocardial fibrosis. There were no adverse events associated with high-dose omega-3 fatty acid therapy. CONCLUSIONS: Treatment of patients with acute myocardial infarction with high-dose omega-3 fatty acids was associated with reduction of adverse left ventricular remodeling, noninfarct myocardial fibrosis, and serum biomarkers of systemic inflammation beyond current guideline-based standard of care. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00729430.

Impact of crossing technique on the incidence of periprocedural myocardial infarction during chronic total occlusion percutaneous coronary intervention.

OBJECTIVES: We sought to evaluate the impact of crossing strategy on the incidence of periprocedural myocardial infarction (PMI) during chronic total occlusion (CTO) percutaneous coronary intervention (PCI). BACKGROUND: The optimal technique for crossing coronary CTOs remains controversial. METHODS: We retrospectively examined the incidence of PMI among 184 consecutive patients who underwent CTO PCI at our institution between 2012 and 2015. Creatine kinase-myocardial band fraction (CK-MB) and troponin were measured before and after PCI in all patients. PMI was defined as CK-MB increase ≥3× upper limit of normal (ULN). RESULTS: Mean age was 65 ± 8 years, 98% of patients were men, 57% had diabetes mellitus, 36% were current smokers, 38% had prior heart failure, 31% had prior coronary artery bypass graft surgery (CABG), and 55% had prior PCI. The retrograde approach was used in 38% of cases. As compared with antegrade wire escalation and antegrade dissection/re-entry, use of the retrograde approach was associated with higher J-CTO (Multicenter CTO Registry of Japan) scores (P < 0.0001), higher frequency of moderate or severe calcification (P = 0.0061), longer CTO length (P < 0.0001), more frequent proximal cap ambiguity (P < 0.0001), and lower technical (P = 0.0007) and procedural (P = 0.0014) success. The frequency of PMI for the antegrade-only and retrograde cases was 10% and 33%, respectively (P = 0.0001). On multivariate analysis, use of the retrograde approach and moderate/severe calcification were independently associated with higher incidence of PMI. CONCLUSIONS: As compared with antegrade-only crossing techniques, the retrograde approach is used in patients with more complex anatomy but may carry higher risk for PMI. © 2016 Wiley Periodicals, Inc.

Long-term outcomes with first- vs. second-generation drug-eluting stents in saphenous vein graft lesions.

BACKGROUND: As compared with bare metal stents, first-generation drug-eluting stents (DES) improved post-procedural outcomes in aortocoronary saphenous vein graft (SVG) lesions, but there is limited information on outcomes after use of second-generation DES in SVGs. METHODS: We compared the outcomes of patients who received first- (n = 81) with those who received second-generation (n = 166) DES in SVG lesions at our institution between 2006 and 2013. Major adverse cardiac events (MACE) were defined as the composite of all-cause death, myocardial infarction, and target vessel revascularization. RESULTS: Mean age was 66.0 ± 8.1 years and 97.6% of the patients were men. Mean SVG age was 11.1 ± 0.4 years. First-generation DES were sirolimus-eluting (n = 17) and paclitaxel-eluting (n = 64) stents. Second-generation DES were everolimus-eluting (n = 115) and zotarolimus-eluting (n = 51) stents. Median follow-up was 41 months. At 2-years post-procedure, patients with first- and second-generation DES had similar rates of death (20.91% vs. 20.27%, P = 0.916), target lesion revascularization (16.39% vs. 20.00%, P = 0.572), target vessel revascularization (20.97% vs. 23.16%, P = 0.747), myocardial infarction (26.15% vs. 23.00%, P = 0.644), and MACE (43.5% vs. 40.87%, P = 0.707), respectively. CONCLUSIONS: Outcomes with first- and second-generation DES in SVGs are similar. Novel stent designs are needed to further improve the clinical outcomes in this challenging patient and lesion subgroup. © 2015 Wiley Periodicals, Inc.

Temporal trends of fluoroscopy time and contrast utilization in coronary chronic total occlusion revascularization: insights from a multicenter United States registry.

BACKGROUND: The impact of operator experience on fluoroscopy time and contrast utilization during percutaneous coronary intervention (PCI) of coronary chronic total occlusions (CTOs) has received limited study. METHODS: We evaluated temporal trends in fluoroscopy time and contrast utilization among 1,363 consecutive CTO PCIs performed at three US institutions between January 2006 and November 2011. RESULTS: Mean age was 65 ± 11 years, 85% of patients were men, 40% had diabetes, 37% had prior coronary artery bypass graft surgery, and 42% had prior PCI. The CTO target vessel was the right coronary artery (55%), circumflex (23%), left anterior descending artery (21%), and left main or bypass graft (1%). The retrograde approach was used in 34% of all procedures. The technical and procedural success rates were 85.5 and 84.2%, respectively. The mean procedural time, fluoroscopy time, and contrast utilization were 113 ± 61 min, 42 ± 29 min, and 294 ± 158 mL, respectively. Years since initiation of CTO PCI were independently associated with higher technical success rate (odds ratio [OR] = 1.52, 95% confidence interval [CI] = 1.52-1.70, P < 0.001), lower fluoroscopy time (OR = 0.84, 95% CI = 0.75-0.95, P = 0.005), and contrast utilization (OR = 0.84, 95% CI = 0.62-0.79, P < 0.001) during the study period. CONCLUSIONS: Among selected US-based institutions performing CTO PCI, we observed a significant reduction in total fluoroscopy time and contrast utilization paralleled with an improved technical success rate over time.

Frequency and outcomes of aortocoronary dissection during percutaneous coronary intervention of chronic total occlusions: a case series and systematic review of the literature.

BACKGROUND: Aortocoronary dissection can complicate percutaneous coronary intervention (PCI) of chronic total occlusions (CTOs). METHODS: We retrospectively examined the frequency and outcomes of aortocoronary dissection among 336 consecutive CTO PCIs performed at our institution between 2005 and 2012 and performed a systematic review of the published literature. RESULTS: Aortocoronary dissection occurred in six patients (1.8%, 95% confidence intervals 0.7%, 3.8%). All aortocoronary dissections occurred in the right coronary artery (CTO target vessel in five patients and donor vessel in one patient). The baseline clinical characteristics of patients with and without aortocoronary dissection were similar. Compared to patients without, those with aortocoronary dissection were more likely to undergo crossing attempts using the retrograde approach (25% vs. 67%, P = 0.036) and experience a major complication (2.4% vs. 33.3%, P = 0.008). Technical and procedural success rates were similar in both groups. Of the six patients with aortocoronary dissection one underwent emergency coronary bypass graft surgery (CABG), four were treated with ostial stenting, and one was treated conservatively without subsequent adverse clinical outcomes. Systematic literature review provided 107 published cases of aortocoronary dissection during PCI, that occurred mainly in the right coronary artery (74.8%) and were treated with stenting (49.5%), emergency CABG (29%), or conservatively (21.5%). CONCLUSIONS: Aortocoronary dissection is an infrequent complication of CTO PCI and although it can be treated with stents in most patients, it may infrequently require emergency CABG.

Low molecular weight dextran provides similar optical coherence tomography coronary imaging compared to radiographic contrast media.

BACKGROUND: Optical coherence tomography (OCT) coronary imaging requires displacement of red blood cells from the vessel lumen. This is usually accomplished using radiographic contrast. Low molecular weight dextran has low cost and is safe in low volumes. In the present study, we compared dextran with contrast for coronary OCT imaging. METHODS: Fifty-one vessels in 26 patients were sequentially imaged using manual injection of radiographic contrast (iodixanol) and dextran. OCT images were analyzed at 1 mm intervals to determine the image clarity (defined as a visible lumen border > 270°) and to measure the lumen area and lumen diameter. To correct for the refractive index of dextran, the dextran area measurements were multiplied by 1.117 and the dextran length measurements were multiplied by 1.057. RESULTS: A total of 3,418 cross-sections (1,709 with contrast and 1,709 with dextran) were analyzed. There were no complications related to OCT imaging or to contrast or dextran administration. Clear image segments were observed in 97.0% vs. 96.7% of the cross-sections obtained with contrast and dextran, respectively (P = 0.45). The mean lumen areas were also similar: 6.69 ± 1.95 mm(2) with iodixanol vs. 7.06 ± 2.06 mm(2) with dextran (correlation coefficient 0.984). CONCLUSIONS: The image quality and measurements during OCT image acquisition are similar for dextran and contrast. Dextran could be used instead of contrast for OCT imaging, especially in patients in whom contrast load minimization is desired.

Prevalence and management of coronary chronic total occlusions in a tertiary Veterans Affairs hospital.

OBJECTIVES: We sought to determine the contemporary prevalence and management of coronary chronic total occlusions (CTO) in a veteran population. BACKGROUND: The prevalence and management of CTOs in various populations has received limited study. METHODS: We collected clinical and angiographic data in consecutive patients that underwent coronary angiography at our institution between January 2011 and December 2012. Coronary artery disease (CAD) was defined as ≥50% diameter stenosis in ≥1 coronary artery. CTO was defined as total coronary artery occlusion of ≥3 month duration. RESULTS: Among 1,699 patients who underwent angiography during the study period, 20% did not have CAD, 20% had CAD and prior coronary artery bypass graft surgery (CABG), and 60% had CAD but no prior CABG. The prevalence of CTO among CAD patients with and without prior CABG was 89 and 31%, respectively. Compared to patients without CTO, CTO patients had more co-morbidities, more extensive CAD and were more frequently referred for CABG. Percutaneous coronary intervention (PCI) to any vessel was performed with similar frequency in patients with and without CTO (50% vs. 53%). CTO PCI was performed in 30% of patients without and 15% of patients with prior CABG with high technical (82 and 75%, respectively) and procedural success rates (80 and 73%, respectively). CONCLUSIONS: In a contemporary veteran population, coronary CTOs are highly prevalent and are associated with more extensive co-morbidities and higher likelihood for CABG referral. PCI was equally likely to be performed in patients with and without CTO.

Long-term outcomes of successful chronic total occlusion percutaneous coronary interventions using the antegrade and retrograde approach.

OBJECTIVE: To compare long-term clinical outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) using the retrograde and antegrade approach. BACKGROUND: There is limited long-term clinical outcomes data on the retrograde approach to CTO PCI. METHODS: We performed a retrospective analysis of the long-term clinical outcomes of 193 consecutive patients who underwent successful CTO PCI at our institution between March 2008 and December 2011. RESULTS: Mean age was 63.6 ± 8.3 years. The target vessel was right coronary artery in 52.6%, left anterior descending artery in 24.5% and circumflex in 21.4% of cases. The retrograde approach was used in 41 patients (21.2%). The mean stent length was longer in the retrograde group (83 ± 32 vs. 64 ± 32 mm, P = 0.001). Two major procedural complications occurred, both in the retrograde group (P = 0.012). During a median follow-up of 2.0 years compared to the antegrade CTO PCI group, patients who underwent retrograde CTO PCI were more likely to undergo target lesion revascularization (TLR) (45.6% vs. 25.7%, P = 0.006). No significant difference was observed in the incidence of all-cause mortality, myocardial infarction, non-target vessel revascularization, or coronary artery bypass graft surgery between the 2 groups. On multivariate analysis, stent length was the only independent predictor of TLR during follow-up. CONCLUSIONS: Retrograde CTO PCI was associated with higher incidence of TLR, but similar incidence of death and myocardial infarction compared to antegrade CTO PCI. These findings likely reflect the higher complexity of CTO lesions treated with the retrograde approach.

Application of the "hybrid approach" to chronic total occlusion interventions: a detailed procedural analysis.

OBJECTIVE: To assess the outcomes of the "hybrid" approach to chronic total occlusion (CTO) percutaneous coronary interventions (PCIs). BACKGROUND: The "hybrid approach" to CTO PCI advocates appropriate and early change of crossing strategy to maximize success, safety, and efficiency. METHODS: We prospectively recorded and analyzed detailed step-by-step procedural data in 73 consecutive CTO PCI cases performed by a single operator between July 2011 and August 2012. RESULTS: Technical success was achieved in 66 of 73 cases (90.4%). Mean patient age was 65 ± 7 years, and 30% had prior coronary artery bypass surgery. Dual injection was used in 78%. The primary approach was retrograde in 9 cases (12.5%) and antegrade in 64 cases (87.5%), of whom 25 cases (39.1%) underwent retrograde attempt after failed antegrade approach. The initial crossing approach was successful in 40 cases (54.8%), but 32 cases (44%) required 3.6 ± 1.4 approach changes (range 2-7). Antegrade wire escalation, antegrade dissection/reentry, and retrograde crossing were utilized in 97.2%, 46.6%, and 46.6% of cases, respectively. Among successful cases, the final CTO crossing technique was antegrade wire escalation in 50.0%, antegrade dissection/reentry in 24.2%, and retrograde in 25.8%. The mean procedure time, fluoroscopy time, and air kerma radiation exposure until CTO crossing or stopping the procedure were 66 ± 55 minutes, 25 ± 23 minutes, and 2.3 ± 1.9 Gray, respectively. Three patients (4.1%) had a major complication. CONCLUSION: In the "hybrid approach" to CTO PCI, changes in crossing strategy were needed in approximately half the cases, resulting in high success and low complication rates.

Effect of six month's treatment with omega-3 acid ethyl esters on long-term outcomes after acute myocardial infarction: The OMEGA-REMODEL randomized clinical trial.

BACKGROUND: Omega-3 polyunsaturated fatty acids (O3-FA) have been shown to reduce inflammation and adverse cardiac remodeling after acute myocardial infarction (AMI). However, the impact of O3-FA on long-term clinical outcomes remains uncertain. AIMS: To investigate the impact of O3-FA on adverse cardiac events in long-term follow up post AMI in a pilot-study. METHODS: Consecutive patients with AMI were randomized 1:1 to receive 6 months of O3-FA (4 g/daily) or placebo in the prospective, multicenter OMEGA-REMODEL trial. Primary endpoint was a composite of major adverse cardiovascular events (MACE) encompassing all-cause death, heart failure hospitalizations, recurrent acute coronary syndrome, and late coronary artery bypass graft (CABG). RESULTS: A total of 358 patients (62.8% male; 48.1 ± 16.1 years) were followed for a median of 6.6 (IQR: 5.0-9.1) years. Among those receiving O3-FA (n = 180), MACE occurred in 65 (36.1%) compared to 62 (34.8%) of 178 assigned to placebo. By intention-to-treat analysis, O3-FA treatment assignment did not reduce MACE (HR = 1.014; 95%CI = 0.716-1.436; p = 0.938), or its individual components. However, patients with a positive response to O3-FA treatment (n = 43), defined as an increase in the red blood cell omega-3 index (O3I) ≥5% after 6 months of treatment, had lower annualized MACE rates compared to those without (2.9% (95%CI = 1.2-5.1) vs 7.1% (95%CI = 5.7-8.9); p = 0.001). This treatment benefit persisted after adjustment for baseline characteristics (HRadjusted = 0.460; 95%CI = 0.218-0.970; p = 0.041). CONCLUSION: In long-term follow-up of the OMEGA-REMODEL randomized trial, O3-FA did not reduce MACE after AMI by intention to treat principle, however, patients who achieved a ≥ 5% increase of O3I subsequent to treatment had favorable outcomes.

Discordant effects of rosiglitazone on novel inflammatory biomarkers.

BACKGROUND: Although rosiglitazone favorably affects myriad intermediate markers of atherosclerosis, it appears to increase myocardial infarction (MI) risk. We analyzed the effects of rosiglitazone on a panel of 8 novel circulating biomarkers, 4 of which are independently associated with atherosclerosis: lymphotoxin ß receptor, peptidoglycan recognition protein 1, chemokine ligand 23, and soluble receptor for advanced glycation end products (sRAGE) as well as on high-sensitivity C-reactive protein (hs-CRP). METHODS: Blood samples were analyzed at baseline and after 6 months of study treatment from subjects with type 2 diabetes with or at high risk for coronary artery disease in a randomized trial comparing rosiglitazone versus placebo. RESULTS: Data from 111 subjects (rosiglitazone 55, placebo 56) were analyzed. Mean age was 56 years, 41% were women, and 66% were nonwhite. Compared with baseline values, rosiglitazone adversely affected levels of lymphotoxin ß receptor (1.7 vs 2.4 ng/mL, P = .002), peptidoglycan recognition protein 1 (29.0 vs 30.1 ng/mL, P = .01), and chemokine ligand 23 (0.76 vs 0.84 ng/mL, P = .02) and favorably affected levels of sRAGE (inversely associated with atherosclerosis, 1.1 vs 1.4 ng/mL, P = .003) and hs-CRP (0.42 vs 0.31 ng/mL, P = .02); no changes were observed with rosiglitazone in the other biomarkers. In the placebo group, change was observed only for sRAGE (1.0 vs 1.1 ng/mL, P = .046). CONCLUSION: Rosiglitazone adversely affected 3 novel biomarkers and favorably affected a fourth previously associated with atherosclerosis while improving hs-CRP, as has previously been shown. Whether these complex effects on circulating inflammatory biomarkers contribute to the signal of increased MI risk with rosiglitazone and whether pioglitazone has similar effects warrant further investigation.

Chronic total occlusions: patient selection and overview of advanced techniques.

Percutaneous treatment of coronary chronic total occlusions (CTOs) remains challenging, mainly due to difficulty in crossing the lesion. However tremendous progress has been achieved recently with expanded use of the retrograde approach and advanced dissection re-entry techniques. The development of the "hybrid" approach from North American operators has provided practical recommendations on how to select initial and subsequent CTO crossing strategies. Moreover, additional information has emerged on the frequency of CTOs among patients undergoing cardiac catheterization and on the adverse prognostic impact of CTOs on clinical outcomes of patients with ischemic cardiomyopathy who have implantable cardioverter defibrillators. Overall, CTO interventions remain a dynamic area with multiple novel technical and clinical developments.

Cardiac Effects of Long-Duration Space Flight.

BACKGROUND: Ventricular mass responds to changes in physical activity and loading, with cardiac hypertrophy after exercise training, and cardiac atrophy after sustained inactivity. Ventricular wall stress (ie, loading) decreases during microgravity. Cardiac atrophy does not plateau during 12 weeks of simulated microgravity but is mitigated by concurrent exercise training. OBJECTIVES: The goal of this study was to determine whether the current exercise countermeasures on the International Space Station (ISS) offset cardiac atrophy during prolonged space flight. METHODS: We measured left ventricular (LV) and right ventricular (RV) mass and volumes (via magnetic resonance imaging) in 13 astronauts (4 females; age 49 ± 4 years), between 75 and 60 days before and 3 days after 155 ± 31 days aboard the ISS. Furthermore, we assessed total cardiac work between 21 and 7 days before space flight and 15 days before the end of the mission. Data were compared via paired-samples t-tests. RESULTS: Total cardiac work was lower during space flight (P = 0.008); however, we observed no meaningful difference in LV mass postflight (pre: 115 ± 30 g vs post: 118 ± 29 g; P = 0.053), with marginally higher LV stroke volume (P = 0.074) and ejection fraction postflight (P = 0.075). RV mass (P = 0.999), RV ejection fraction (P = 0.147), and ventricular end-diastolic (P = 0.934) and end-systolic volumes (P = 0.145) were not different postflight. There were strong positive correlations between the relative change in LV mass with the relative changes in total cardiac output (r = 0.73; P = 0.015) and total cardiac work (r = 0.53; P = 0.112). CONCLUSIONS: The current exercise countermeasures used on the ISS appear effective in offsetting reductions in cardiac mass and volume, despite overall reductions in total cardiac work, during prolonged space flight.

Sex-Specific Stress Perfusion Cardiac Magnetic Resonance Imaging in Suspected Ischemic Heart Disease: Insights From SPINS Retrospective Registry.

BACKGROUND: Cardiovascular disease (CVD) remains the leading cause of mortality in women, but current noninvasive cardiac imaging techniques have sex-specific limitations. OBJECTIVES: In this study, the authors sought to investigate the effect of sex on the prognostic utility and downstream invasive revascularization and costs of stress perfusion cardiac magnetic resonance (CMR) for suspected CVD. METHODS: Sex-specific prognostic performance was evaluated in a 2,349-patient multicenter SPINS (Stress CMR Perfusion Imaging in the United States [SPINS] Study) Registry. The primary outcome measure was a composite of cardiovascular death and nonfatal myocardial infarction; secondary outcomes were hospitalization for unstable angina or heart failure, and late unplanned coronary artery bypass grafting. RESULTS: SPINS included 1,104 women (47% of cohort); women had higher prevalence of chest pain (62% vs 50%; P < 0.0001) but lower use of medical therapies. At the 5.4-year median follow-up, women with normal stress CMR had a low annualized rate of primary composite outcome similar to men (0.54%/y vs 0.75%/y, respectively; P = NS). In contrast, women with abnormal CMR were at higher risk for both primary (3.74%/y vs 0.54%/y; P < 0.0001) and secondary (9.8%/y vs 1.6%/y; P < 0.0001) outcomes compared with women with normal CMR. Abnormal stress CMR was an independent predictor for the primary (HR: 2.64 [95% CI: 1.20-5.90]; P = 0.02) and secondary (HR: 2.09 [95% CI: 1.43-3.08]; P < 0.0001) outcome measures. There was no effect modification for sex. Women had lower rates of invasive coronary angiography (3.6% vs 7.3%; P = 0.0001) and downstream costs ($114 vs $171; P = 0.001) at 90 days following CMR. There was no effect of sex on diagnostic image quality. CONCLUSIONS: Stress CMR demonstrated excellent prognostic performance with lower rates of invasive coronary angiography referral in women. Stress CMR should be considered as a first-line noninvasive imaging tool for the evaluation of women. (Stress CMR Perfusion Imaging in the United States [SPINS] Study [SPINS]; NCT03192891).

Prognostic Value of Stress Cardiac Magnetic Resonance in Patients With Known Coronary Artery Disease.

OBJECTIVES: This study sought to determine whether stress cardiac magnetic resonance (CMR) provides clinically relevant risk reclassification in patients with known coronary artery disease (CAD) in a multicenter setting in the United States. BACKGROUND: Despite improvements in medical therapy and coronary revascularization, patients with previous CAD account for a disproportionately large portion of CV events and pose a challenge for noninvasive stress testing. METHODS: From the Stress Perfusion Imaging in the United States (SPINS) registry, we identified consecutive patients with documented CAD who were referred to stress CMR for evaluation of myocardial ischemia. The primary outcome was nonfatal myocardial infarction (MI) or cardiovascular (CV) death. Major adverse CV events (MACE) included MI/CV death, hospitalization for heart failure or unstable angina, and late unplanned coronary artery bypass graft. The prognostic association and net reclassification improvement by ischemia for MI/CV death were determined. RESULTS: Out of 755 patients (age 64 ± 11 years, 64% male), we observed 97 MI/CV deaths and 210 MACE over a median follow-up of 5.3 years. Presence of ischemia demonstrated a significant association with MI/CV death (HR: 2.30; 95% CI: 1.54-3.44; P < 0.001) and MACE (HR: 2.24 ([95% CI: 1.69-2.95; P < 0.001). In a multivariate model adjusted for CV risk factors, ischemia maintained strong association with MI/CV death (HR: 1.84; 95% CI: 1.17-2.88; P = 0.008) and MACE (HR: 1.77; 95% CI: 1.31-2.40; P < 0.001) and reclassified 95% of patients at intermediate pretest risk (62% to low risk, 33% to high risk) with corresponding changes in the observed event rates of 1.4% and 5.3% per year for low and high post-test risk, respectively. CONCLUSIONS: In a multicenter cohort of patients with known CAD, CMR-assessed ischemia was strongly associated with MI/CV death and reclassified patient risk beyond CV risk factors, especially in those considered to be at intermediate risk. Absence of ischemia was associated with a <2% annual rate of MI/CV death. (Stress CMR Perfusion Imaging in the United States [SPINS] Study; NCT03192891).

Randomized comparison of the effects of rosiglitazone vs. placebo on peak integrated cardiovascular performance, cardiac structure, and function.

AIMS: To assess the effect of rosiglitazone on cardiovascular performance and cardiac function. METHODS AND RESULTS: One hundred and fifty type 2 diabetes patients with cardiovascular disease (CVD) or ≥ 1 other CVD risk factor were randomized to receive rosiglitazone vs. placebo for 6 months. The primary outcome was peak oxygen uptake indexed to fat-free mass (VO(2peak)-FFM) during maximum exercise. A subset of 102 subjects underwent cardiac magnetic resonance imaging (cMRI). On hundred and eight subjects completed the study, including 75 completing the cMRI substudy. No significant differences were observed in mean VO(2peak)-FFM between rosiglitazone and placebo (26.1 ± 7.0 vs. 27.6 ± 6.6 mL/kg-FFM/min; P = 0.26). Compared with placebo, the rosiglitazone group had lower hematocrit (38 vs. 41%; P < 0.001) and more peripheral oedema (53.7 vs. 33.3%; P = 0.03). In the cMRI substudy, compared with placebo, the rosiglitazone group had larger end-diastolic volume (128.1 vs. 112.0 mL; P = 0.01) and stroke volume (83.7 vs. 72.9 mL; P = 0.01), and a trend toward increased peak ventricular filling rate (79.4 vs. 60.5; P = 0.07). CONCLUSION: Rosiglitazone increased peripheral oedema but had no pernicious effects on cardiovascular performance or cardiac function, with modest improvement in selected cMRI measures. Changes in indirect markers of plasma volume suggest expansion with rosiglitazone. TRIAL REGISTRATION: clinicaltrials.gov identifier: NCT00424762.