Successful left ventricular lead placement by way of an azygos vein for a patient performing cardiac resynchronization therapy implantation with an occluded left subclavian vein: A case report.

Central venous obstruction following pacemaker implantation is not uncommon and can prove challenging in the case of a system upgrade to a cardiac resynchronization therapy pacemaker (CRT-P). We describe the case of a patient who underwent a successful upgrading procedure of a pacemaker to a CRT-P in the presence of an occluded left subclavian vein and superior vena cava, using collateral veins that drained into right atrium.

Impact of the Temporal Distribution of Coronary Artery Disease Progression on Subsequent Consequences in Patients with Acute Coronary Syndrome.

The late consequences of acute coronary syndrome (ACS) have been underestimated. We hypothesized that the temporal distribution of the clinically silent coronary artery disease progression (CP) is associated with the subsequent consequences of ACS.We studied 243 patients (202 men, 64 ± 10 years) with ACS undergoing percutaneous coronary intervention (PCI) during initial hospitalization. All patients underwent serial coronary angiograms (CAGs) immediately before PCI and at 7 ± 3 and 60 ± 10 months after presentation. CP was defined as an increase ≥ 15% in stenosis severity of the lesion between 2 serial CAGs. The impact of CP between each 2 serial CAGs on subsequent major adverse cardiovascular and cerebrovascular events (MACCEs) after the final CAG was examined using multivariate Cox and propensity-matched analyses.During the median follow-up duration after the final CAG of 67 months, 76 MACCEs (31.3%) were observed. Multivariate Cox proportional hazards analysis revealed that CP between the first and second CAGs (hazard ratio [HR], 2.28; 95% confidence interval [CI], 1.32-3.94; P = 0.003) and CP between the second and final CAGs (HR, 1.96; 95% CI, 1.20-3.21; P = 0.008) were independently associated with a higher rate of MACCEs beyond the final CAG. Consistent results were obtained in the propensity score-matched analyses.CP in both the early (0-7 months) and late phases (7-60 months) were independently associated with subsequent clinical events. This may indicate the prognostic significance of persistent widespread coronary disease activity following presentation in patients with ACS undergoing PCI.

Distinction Between Precapillary and Postcapillary Pulmonary Hypertension by the Atrial Volume Ratio on Transthoracic Echocardiography.

OBJECTIVES: The differential diagnosis between precapillary and postcapillary pulmonary hypertension (PH) is important for deciding on the appropriate therapeutic strategy. The aim of this study was to assess whether the atrial volume ratio can differentiate precapillary and post-capillary PH. METHODS: Seventy-seven patients with PH who underwent transthoracic echocardiography (TTE) and right heart catheterization were retrospectively studied. Pulmonary hypertension was defined as a mean pulmonary arterial pressure of 25 mm Hg or higher by right heart catheterization. Patients with a pulmonary capillary wedge pressure higher than 15 mm Hg were classified as having postcapillary PH, and patients with a pulmonary capillary wedge pressure of 15 mm Hg or lower were classified as having precapillary PH. The atrial volume ratio derived from TTE was defined as right atrial volume divided by left atrial volume. RESULTS: Forty-four (57%) of 77 patients had precapillary PH by the right heart catheterization classification. The atrial volume ratio was significantly higher in precapillary PH than in postcapillary PH (1.03 ± 0.69 versus 0.50 ± 0.19; P < .001). The area under the receiver operating characteristic curve of the atrial volume ratio for detecting postcapillary PH was 0.84 (95% confidence interval: 0.75-0.93). Adding the atrial volume ratio to the left ventricular ejection fraction yielded a high area under the curve of 0.90 (95% confidence interval, 0.83-0.96) for distinguishing precapillary and postcapillary PH. CONCLUSIONS: The atrial volume ratio assessed by TTE might be useful for differential diagnosis between precapillary and postcapillary PH.

ST-segment category at acute presentation is associated with the time course of coronary artery disease progression in patients with acute coronary syndromes.

BACKGROUND: Several studies have shown higher early mortality for ST-segment elevation acute coronary syndrome (STEACS), but late mortality remains consistently higher for non-ST-segment elevation acute coronary syndrome (NSTEACS). We hypothesized that ST-segment category at acute presentation is associated with the time course of coronary artery disease progression (CP) of nonculprit lesions in patients with acute coronary syndrome (ACS). METHODS: A total of 226 patients (182 men, age 65 ± 10 years) with STEACS (n = 95) or NSTEACS (n = 131) who underwent percutaneous coronary intervention (PCI) during initial hospitalization were studied. All patients underwent serial coronary angiograms (CAGs) performed immediately before PCI and at 7 ± 3 months and 60 ± 10 months after presentation. CP was defined as an increase in stenosis severity >15% of a nonculprit lesion between 2 serial CAGs. RESULTS: The rate of CP between the first and second CAGs did not differ by ST-segment category at acute presentation. Compared to STEACS, NSTEACS had a higher rate of CP between the second and final CAGs (27.4 vs. 42.7%, P = 0.018). Multivariate analysis showed that the independent predictors of CP between the second and final CAGs were NSTEACS (odds ratio 2.709, P = 0.003), estimated glomerular filtration rate <60 ml/min/1.73 m2 (odds ratio 2.447, P = 0.015), and diabetes mellitus (odds ratio 2.135, P = 0.021). CONCLUSIONS: Irrespective of conventional risk factors and angiographic findings, ST-segment category at initial presentation is associated with the persistency of widespread coronary disease activity following presentation in ACS patients undergoing PCI. This may partly explain the time-dependent differences in outcomes of patients with STEACS and NSTEACS.

A case of complete double aortic arch visualized by transthoracic echocardiography.

A case of double aortic arch that was well visualized using transthoracic echocardiography is reported. A 38-year-old man underwent transthoracic echocardiography for the evaluation of dyspnea. A suprasternal view of transthoracic echocardiography showed the ascending aorta bifurcate to left and right aortic arches, with blood flow from the ascending aorta to bilateral aortic arches. The diagnosis of right side-dominant double aortic arch was made, and the patient's symptom was conceivably related to compression of the trachea due to a vascular ring. This report indicates the potential usefulness of transthoracic echocardiography for noninvasive detection of double aortic arch in adults.

Incremental prognostic value of the SYNTAX score to late gadolinium-enhanced magnetic resonance images for patients with stable coronary artery disease.

The prognostic significance of the SYNTAX (Synergy between PCI with Taxus and cardiac surgery) score has recently been demonstrated in patients with stable multivessel or left main coronary artery disease (CAD). The present study determines whether adding the SYNTAX score to Framingham risk score (FRS), left ventricular ejection fraction (LVEF) and presence of myocardial infarction (MI) by late gadolinium enhancement (LGE) magnetic resonance imaging can improve the risk stratification in patients with stable CAD. We calculated the SYNTAX score in 161 patients with stable CAD (mean age: 66 ± 10 years old). During a mean follow-up of 2.3 years, 56 (35 %) of 161 patients developed cardiovascular events defined as cardiovascular death, non-fatal MI, cerebral infarction, unstable angina pectoris, hospitalization due to heart failure and revascularization. Multivariate Cox regression analysis selected triglycerides [hazard ratio (HR): 1.005 (95 % confidence interval (CI): 1.001-1.008), p < 0.008], presence of LGE [HR: 6.329 (95 % CI: 2.662-15.05), p < 0.001] and the SYNTAX score [HR: 1.085 (95 % CI: 1.044-1.127), p < 0.001] as risk factors for future cardiovascular events. Adding the SYNTAX score to FRS, EF and LGE significantly improved the net reclassification index (NRI) [40.4 % (95 % CI: 18.1-54.8 %), p < 0.05] with an increase in C-statistics of 0.089 (from 0.707 to 0.796). An increase in C-statistics and significant improvement of NRI showed that adding the SYNTAX score to the FRS, LVEF and LGE incrementally improved risk stratification in patient with stable CAD.

Prognostic value of cardiovascular magnetic resonance derived right ventricular function in patients with interstitial lung disease.

BACKGROUND: Cardiovascular magnetic resonance (CMR) provides non-invasive and more accurate assessment of right ventricular (RV) function in comparison to echocardiography. Recent study demonstrated that assessment of RV function by echocardiography was an independent predictor for mortality in patients with interstitial lung disease (ILD). The purpose of this study was to determine the prognostic significance of CMR derived RV ejection fraction (RVEF) in ILD patients. METHODS: We enrolled 76 patients with ILD and 24 controls in the current study. By using 1.5 T CMR scanner equipped with 32 channel cardiac coils, we performed steady-state free precession cine CMR to assess the RVEF. RV systolic dysfunction (RVSD) was defined as RVEF ≤45.0% calculated by long axis slices. Pulmonary hypertension (PH) was defined as mean pulmonary artery pressure (mPAP) of more than 25 mmHg at rest in the setting of pulmonary capillary wedge pressure ≤15 mmHg. RESULTS: The median RVEF was 59.2% in controls (n = 24), 53.8% in ILD patients without PH (n = 42) and 43.1% in ILD patients with PH (n = 13) (p < 0.001 by one-way ANOVA). During a mean follow-up of 386 days, 18 patients with RVSD had 11 severe events (3 deaths, 3 right heart failure, 3 exacerbation of dyspnea requiring oxygen, 2 pneumonia requiring hospitalization). In contrast, only 2 exacerbation of dyspnea requiring oxygen were observed in 58 patients without RVSD. Multivariate Cox regression analysis showed that RVEF independently predicted future events, after adjusting for age, sex and RVFAC by echocardiography (hazard ratio: 0.889, 95% confidence interval: 0.809-0.976, p = 0.014). CONCLUSIONS: The current study demonstrated that RVSD in ILD patients can be clearly detected by cine CMR. Importantly, low prevalence of PH (17%) indicated that population included many mild ILD patients. CMR derived RVEF might be useful for the risk stratification and clinical management of ILD patients.

Glycemic Variability on Continuous Glucose Monitoring System Predicts Rapid Progression of Non-Culprit Lesions in Patients With Acute Coronary Syndrome.

BACKGROUND: Although rapid progression (RP) of coronary artery disease (CAD) has been shown to be a powerful predictor of cardiovascular events, predictors of RP are not fully understood in patients with acute coronary syndrome (ACS). METHODS AND RESULTS: We prospectively investigated the clinical impact of glycemic variability (GV), as determined on continuous glucose monitoring system (CGMS), on RP of non-culprit lesions in 88 patients with ACS. RP was defined as ≥10% diameter reduction in a pre-existing stenosis ≥50%; ≥30% diameter reduction in a stenosis <50%; development of a new stenosis ≥30% in a previously normal segment; or progression of any stenosis to total occlusion. Patients were classified into 2 groups according to the presence (progressor, n=20) or absence (non-progressor, n=68) of RP. All patients were equipped with a CGMS during the stable phase, and mean amplitude of glycemic excursion (MAGE) was calculated as a marker of GV. Mean MAGE was significantly higher in progressors than in non-progressors (55±19 mg/dl vs. 37±18 mg/dl, P<0.01). On multiple logistic regression analysis, MAGE was an independent predictor of RP (odds ratio, 1.06 per 1 mg/dl; P<0.01). CONCLUSIONS: MAGE early after the onset of ACS is a predictor of RP of non-culprit lesions.

Successful Catheter Ablation for Paroxysmal Supraventricular Tachycardia with Two Alternating Cycle Lengths.

A 62-year-old male was transferred to our hospital complaining of palpitations. His heart rate was 185/min. Electrocardiogram showed a narrow QRS regular tachycardia and the tachycardia changed spontaneously to another narrow QRS tachycardia with two alternating cycle lengths. The arrhythmia was stopped by the administration of adenosine triphosphate. Findings from electrophysiological study suggested that there was an accessory pathway (AP) and dual atrioventricular (AV) nodal pathways. After AP ablation, any other tachyarrythmias were not induced. We supposed that the tachycardia was paroxysmal supraventricular tachycardia involving AP and anterograde conduction alternating between slow and fast AV nodal pathways.

Relationship between coronary flow reserve evaluated by phase-contrast cine cardiovascular magnetic resonance and serum eicosapentaenoic acid.

BACKGROUND: Long-term intake of long-chain n-3 polyunsaturated fatty acids (n-3 PUFAs), especially eicosapentaenoic acid (EPA) is associated with a low risk for cardiovascular disease. Phase-contrast cine cardiovascular magnetic resonance (PC cine CMR) can assess coronary flow reserve (CFR). The present study investigates the relationship between CFR evaluated by PC cine CMR and the serum EPA. METHODS: We studied 127 patients (male, 116 (91%); mean age, 72.2 ± 7.4 years) with known or suspected coronary artery disease (CAD). X-ray coronary angiography revealed no significant coronary arterial stenoses (defined as luminal diameter reduction ≥ 50% on quantitative coronary angiogram (QCA) analysis) in all study participants. Breath-hold PC cine CMR images of the coronary sinus (CS) were acquired to assess blood flow of the CS both at rest and during adenosine triphosphate (ATP) infusion. We calculated CFR as CS blood flow during ATP infusion divided by that at rest. Patients were allocated to groups according to whether they had high (n = 64, EPA ≥ 75.8 µg/mL) or low (n = 63, EPA < 75.8 µg/mL) median serum EPA. RESULTS: CFR was significantly lower in the low, than in the high EPA group (2.54 ± 1.00 vs. 2.91 ± 0.98, p = 0.038). Serum EPA positively correlated with CFR (R = 0.35, p < 0.001). We defined preserved CFR as > 2.5, which is the previously reported lower limit of normal flow reserve without obstructive CAD. Multivariate analysis revealed that EPA is an independent predictor of CFR > 2.5 (odds ratio, 1.01; 95% confidence interval, 1.00 - 1.02, p = 0.008). CONCLUSIONS: The serum EPA is significantly correlated with CFR in CAD patients without significant coronary artery stenosis.

Machine Learning for Prediction of Technical Results of Percutaneous Coronary Intervention for Chronic Total Occlusion.

(1) Background: The probability of technical success in percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) represents essential information for specifying the priority of PCI for treatment selection in patients with CTO. However, the predictabilities of existing scores based on conventional regression analysis remain modest, leaving room for improvements in model discrimination. Recently, machine learning (ML) techniques have emerged as highly effective methods for prediction and decision-making in various disciplines. We therefore investigated the predictability of ML models for technical results of CTO-PCI and compared their performances to the results from existing scores, including J-CTO, CL, and CASTLE scores. (2) Methods: This analysis used data from the Japanese CTO-PCI expert registry, which enrolled 8760 consecutive patients undergoing CTO-PCI. The performance of prediction models was assessed using the area under the receiver operating curve (ROC-AUC). (3) Results: Technical success was achieved in 7990 procedures, accounting for an overall success rate of 91.2%. The best ML model, extreme gradient boosting (XGBoost), outperformed the conventional prediction scores with ROC-AUC (XGBoost 0.760 [95% confidence interval {CI}: 0.740-0.780] vs. J-CTO 0.697 [95%CI: 0.675-0.719], CL 0.662 [95%CI: 0.639-0.684], CASTLE 0.659 [95%CI: 0.636-0.681]; p < 0.005 for all). The XGBoost model demonstrated acceptable concordance between the observed and predicted probabilities of CTO-PCI failure. Calcification was the leading predictor. (4) Conclusions: ML techniques provide accurate, specific information regarding the likelihood of success in CTO-PCI, which would help select the best treatment for individual patients with CTO.

Non-Invasive Evaluation of Patients Undergoing Percutaneous Coronary Intervention for Chronic Total Occlusion.

BACKGROUND: As percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) gains wider acceptance as a therapeutic option for coronary artery disease, the importance of appropriate patient selection has increased. Although cardiovascular magnetic resonance imaging (MRI) allows segmental and quantitative analyses of myocardial ischemia and scar transmurality, it has limitations, including contraindications, cost, and accessibility. This study established a non-invasive method to evaluate patients undergoing CTO-PCI using two-dimensional speckle-tracking echocardiography (2D-STE). METHODS: Overall, we studied 55 patients who underwent successful CTO-PCI. Cardiovascular MRI and 2D-STE were performed before and 8 ± 2 months after CTO-PCI. Segmental findings of strain parameters were compared with those obtained with late gadolinium enhancement and stress-perfusion MRI. RESULTS: With a cutoff of -10.7, pre-procedural circumferential strain (CS) showed reasonable sensitivity (71%) and specificity (73%) for detecting segments with transmural scar. The discriminatory ability of longitudinal strain (LS) for segments with transmural scar significantly improved during follow-up after successful CTO-PCI in the territory of the recanalized artery (area under the curve (AUC) 0.70 vs. 0.80, p < 0.001). LS accuracy was lower than that of CS at baseline (AUC 0.70 vs. 0.79, p = 0.048), and was increased at follow-up (AUC 0.80 vs. 0.82, p = 0.81). Changes in myocardial perfusion reserve from baseline to follow-up were significantly associated with those in LS but not in CS. CONCLUSIONS: Use of 2D-STE may allow the non-invasive evaluation of patients undergoing CTO-PCI to assess the indication before the procedure and treatment effects at follow-up.

Impact of high-responsiveness to dual antiplatelet therapy on bleeding complications in patients receiving drug-eluting stents.

BACKGROUND: Few studies have examined whether high-responsiveness to antiplatelet therapy is associated with an increased risk of bleeding in patients receiving dual antiplatelet therapy. METHODS AND RESULTS: Elective drug-eluting stent implantation was performed in 184 patients treated with aspirin and a thienopyridine (200 mg/day of ticlopidine or 75 mg/day of clopidogrel). The subjects were divided into 3 groups according to post-treatment platelet reactivity before stenting as measured by the response to adenosine diphosphate: the 1(st) quartile group was defined as high-responders, the 4(th) as low-responders, and the other 2 quartiles as middle-responders. Major bleeding occurred more frequently in high-responders than in middle- or low-responders during an average of 16 months' follow-up (15 vs 4, 2%, P=0.02). High-responsiveness was the independent predictor of major bleeding (odds ratio 4.26, P=0.03). Adverse cardiac events were less frequent in high- and middle-responders than in low-responders (24, 16 vs 37%, P=0.02). Middle-responders had better net clinical outcomes, defined as the sum of major bleeding and adverse cardiac events, than did high- or low-responders (21 vs 39, 39%, P=0.02). CONCLUSIONS: In the present study high-responsiveness to antiplatelet therapy was associated with an increased risk of bleeding with no reduction in adverse cardiac events. Measuring platelet reactivity may be useful for risk stratification according to bleeding complications, as well as adverse cardiac events, in patients treated with drug-eluting stents.

Scoring System for Identification of "Survival Advantage" after Successful Percutaneous Coronary Intervention in Patients with Chronic Total Occlusion.

BACKGROUND: Percutaneous coronary intervention (PCI) is widely used in patients with chronic total occlusion (CTO), but its benefit in improving long-term outcomes is controversial. We aimed to develop a prediction score for grading "survival advantage" conferred by successful results of CTO-PCI and a scoring system for prediction of the influence of CTO-PCI results on major adverse cardiac and cerebrovascular events (MACCEs). METHODS: Follow-up data of 2625 patients who underwent CTO-PCI at 65 Japanese centers were analyzed. An integer scoring system was developed by including statistical effect modifiers on the association between successful CTO-PCI and one-year mortality. RESULTS: Follow-up at 12 months was completed in 2034 patients. During follow-up, 76 deaths (3.7%) occurred. Patients with successful CTO-PCI had a better one-year survival than patients with failed CTO-PCI (log rank P = 0.016). Effect modifiers for the association between successful procedure and one-year mortality included diabetes (P interaction = 0.043), multivessel disease (P interaction = 0.175), Canadian Cardiovascular Society class ≥2 (P interaction = 0.088), and prior myocardial infarction (MI) (P interaction = 0.117). Each component was assigned a single point and summed to develop the scoring system. The patients were then categorized to specify the prediction of survival advantage by successful PCI: ≤2 (normal) and ≥3 (distinct). The differences in one-year mortality between patients with successful and failed treatment were -0.7% and 11.3% for normal and distinct score categories, respectively. In the scoring system for MACCE, score components were prior MI (P interaction = 0.19), left anterior descending artery (LAD)-CTO (P interaction = 0.079), and reattempt of CTO-PCI (P interaction = 0.18). The differences in one-year MACCEs between successful and failed patients for each score category (0, 1, and ≥2) were -1.7%, 7.5%, and 15.1%, respectively. CONCLUSIONS: The novel scoring system assessing the advantage of successful PCI can be easily applied in patients with CTO. It is a valid instrument for clinical decision-making while assessing the survival advantage of CTO-PCI and the influence of procedural results on MACCEs.

Stress Perfusion Coronary Flow Reserve Versus Cardiac Magnetic Resonance for Known or Suspected CAD.

BACKGROUND: Phase-contrast (PC) cine magnetic resonance imaging (MRI) of the coronary sinus is a noninvasive method to quantify coronary flow reserve (CFR). OBJECTIVES: This study sought to compare the prognostic value of CFR by cardiac magnetic resonance (CMR) and stress perfusion CMR to predict major adverse cardiac events (MACE). METHODS: Participants included 276 patients with known coronary artery disease (CAD) and 400 with suspected CAD. CFR was calculated as myocardial blood flow during adenosine triphosphate infusion divided by myocardial blood flow at rest using PC cine MRI of the coronary sinus. RESULTS: During a median follow-up of 2.3 years, 47 patients (7%) experienced MACE. Impaired CFR (<2.0) and >10% ischemia on stress perfusion CMR were significantly associated with MACE in patients with known CAD (hazard ratio [HR]: 5.17 and HR: 5.10, respectively) and suspected CAD (HR: 14.16 and HR: 6.50, respectively). The area under the curve for predicting MACE was 0.773 for CFR and 0.731 for stress perfusion CMR (p = 0.58) for patients with known CAD, and 0.885 for CFR and 0.776 for stress perfusion CMR (p = 0.059) in the group with suspected CAD. In patients with known CAD, sensitivity, specificity, and positive and negative predictive values to predict MACE were 64%, 91%, 38%, and 97%, respectively, for CFR, and 82%, 59%, 15%, and 97%, respectively, for stress perfusion CMR. In the suspected CAD group, these values were 65%, 99%, 80%, and 97%, respectively, for CFR, and 72%, 83%, 22%, and 98%, respectively, for stress perfusion CMR. CONCLUSIONS: The predictive values of CFR and stress perfusion CMR for MACE were comparable in patients with known CAD. In patients with suspected CAD, CFR showed higher HRs and areas under the curve than stress perfusion CMR, suggesting that CFR assessment by PC cine MRI might provide better risk stratification for patients with suspected CAD.

Prediction of functional recovery after percutaneous coronary revascularization for chronic total occlusion using late gadolinium enhanced magnetic resonance imaging.

BACKGROUND: Limited data are available regarding the prediction for functional recovery using late gadolinium enhanced magnetic resonance imaging (LGE MRI) after coronary revascularization for chronic total occlusion (CTO PCI). METHODS: We studied 59 patients (mean age, 66±11 years) who underwent successful CTO PCI. Two-dimensional echocardiography and strain measurements were performed before and 8±2 months after CTO PCI. The findings of segmental assessment were compared with the extent of LGE MRI using a 16-segment model. RESULTS: From baseline to follow-up, ejection fraction (54.2±12.1% to 56.1±10.6%, p=0.010), global longitudinal strain (LS) (-15.1±5.1 to -16.7±5.1, p<0.001), global circumferential strain (CS) (-14.0±4.9 to -15.9±4.9, p<0.001), and wall motion score (WMS) index (1.45±0.53 to 1.33±0.39, p=0.014) significantly improved. In the territory of the CTO vessel, LS and CS significantly improved in segments of LGE ≤50%, but not in segments of LGE >50%. However, WMS improved only in segments of LGE 1-25%. At baseline and at follow-up, CS allowed better discrimination of segments of LGE >50% than WMS [at baseline; area under the curve (AUC) 0.79 vs. 0.68, respectively, p=0.001: at follow-up; AUC 0.84 vs. 0.69, respectively, p<0.001). Discriminatory ability of LS for segments of LGE >50% significantly improved from baseline to follow-up (AUC 0.73 vs. 0.83, p<0.001). CONCLUSIONS: The cut-off value of the extent of LGE MRI is 50% to detect segments that will functionally recover after CTO PCI. Change in LS was more sensitive for removal of ischemia by CTO PCI, indicating the utility of LS to monitor the therapeutic effects of CTO recanalization.

Impact of Hemodialysis on Procedural Outcomes of Percutaneous Coronary Intervention for Chronic Total Occlusion: Insights From the Japanese Multicenter Registry.

BACKGROUND: Among patients treated with percutaneous coronary intervention for chronic total occlusion (CTO-PCI), patients on long-term hemodialysis are at significantly high risk for cardiovascular mortality and morbidity. However, clinical or angiographic predictors that might aid in better patient selection remain unclear. We aimed to assess the acute impact of hemodialysis in patients who underwent CTO-PCI. METHODS AND RESULTS: The Retrograde Summit registry is a multicenter, prospective registry of patients undergoing CTO-PCI at 65 Japanese centers. Patient characteristics and procedural outcomes of 4749 patients were analyzed, according to the presence (n=313) or absence (n=4436) of baseline hemodialysis. A prediction model for technical failure among hemodialysis patients was also developed. The technical success rate of CTO-PCI was significantly lower in hemodialysis than in nonhemodialysis patients (78.0% versus 89.1%, P<0.001). The rates of in-hospital major adverse cardiac and cerebrovascular events were similar between the 2 groups (1.6% versus 0.9%, P=0.24). Irrespective of clinical/angiographic characteristics or previously developed scoring systems, hemodialysis independently predicted technical failure for CTO-PCI. Among hemodialysis patients, predictors of technical failure were blunt stump (odds ratio 2.45, 95% confidence interval, 1.15-5.21, P=0.021), severe lesion calcification (odds ratio 2.50, 95% confidence interval, 1.19-5.24, P=0.015), and absence of diabetes mellitus (odds ratio 3.15, 95% confidence interval, 1.49-6.64, P=0.003). In hemodialysis patients without these predictors, the technical success rate was 96.2%. CONCLUSIONS: Hemodialysis is significantly associated with technical failure. Contemporary CTO-PCI seems feasible and safe in selected hemodialysis patients.

Higher CHADS2 score is associated with impaired coronary flow reserve: A study using phase contrast cine magnetic resonance imaging.

BACKGROUND: The presence of coronary microvascular dysfunction (CMD) is an important prognostic marker for coronary artery disease (CAD) patients. The purpose of this study was to investigate whether the CHADS2 score is associated with CMD evaluated by magnetic resonance imaging (MRI). MATERIALS AND METHODS: One hundred forty three patients with known or suspected CAD (mean age 70.3±9.5years) were enrolled. All patients did not have any significant coronary stenosis on X-ray coronary angiography (CAG) at the time of MRI acquisition. By using a 1.5T MRI scanner, breath-hold phase contrast cine MRI images of coronary sinus (CS) were obtained to assess the blood flow of CS both at rest and during adenosine triphosphate (ATP) infusion. Coronary flow reserve (CFR) was calculated as CS blood flow during ATP infusion divided by CS blood flow at rest. CMD was defined as CFR<2.5 according to a previous study. Patients were allocated to four groups based on the CHADS2 score (group1: CHADS2 score=0, group2: CHADS2 score=1; group3: CHADS2 score=2, and group4: CHADS2 score≥3). RESULTS: Mean CFR was 2.81±0.95 (77.6±32.7mL/min at rest; 208.2±86.5mL/min during ATP infusion, p<0.001). Patients with higher CHAD2 score had lower CFR. In the multiple logistic regression analysis, CHADS2 score was independently associated with CFR (odds ratio=0.61, 95% confidence interval: 0.37-0.99, p=0.049). CONCLUSIONS: Higher CHADS2 score was significantly associated with lower CFR evaluated by phase contrast cine MRI.

Impairment of Coronary Flow Reserve Evaluated by Phase Contrast Cine-Magnetic Resonance Imaging in Patients With Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Phase contrast (PC) cine-magnetic resonance imaging (MRI) of the coronary sinus allows for noninvasive evaluation of coronary flow reserve (CFR), which is an index of left ventricular microvascular function. The objective of this study was to investigate coronary flow reserve in patients with heart failure with preserved ejection fraction (HFpEF). METHODS AND RESULTS: We studied 25 patients with HFpEF (mean and SD of age: 73±7 years), 13 with hypertensive left ventricular hypertrophy (LVH) (67±10 years), and 18 controls (65±15 years). Breath-hold PC cine-MRI images of the coronary sinus were obtained to assess blood flow at rest and during ATP infusion. CFR was calculated as coronary sinus blood flow during ATP infusion divided by coronary sinus blood flow at rest. Impairment of CFR was defined as CFR <2.5 according to a previous study. The majority (76%) of HFpEF patients had decreased CFR. CFR was significantly decreased in HFpEF patients in comparison to hypertensive LVH patients and control subjects (CFR: 2.21±0.55 in HFpEF vs 3.05±0.74 in hypertensive LVH, 3.83±0.73 in controls; P<0.001 by 1-way ANOVA). According to multivariable linear regression analysis, CFR independently and significantly correlated with serum brain natriuretic peptide level (ß=-68.0; 95% CI, -116.2 to -19.7; P=0.007). CONCLUSIONS: CFR was significantly lower in patients with HFpEF than in hypertensive LVH patients and controls. These results indicated that impairment of CFR might be a pathophysiological factor for HFpEF and might be related to HFpEF disease severity.

Inhibition of DPP-4 by alogliptin improves coronary flow reserve and left ventricular systolic function evaluated by phase contrast cine magnetic resonance imaging in patients with type 2 diabetes and coronary artery disease.

BACKGROUND: The present study determined whether dipeptidyl peptidase-4 (DPP-4) inhibition by alogliptin improves coronary flow reserve (CFR) and left ventricular election fraction (LVEF) in patients with type 2 DM and CAD. MATERIALS AND METHODS: Twenty patients with type 2 DM and known or suspected CAD were randomly allocated to receive diet therapy plus alogliptin (n=10; mean age, 73.3±6.6y) or a control group given diet therapy and glimepiride (n=10; mean age, 76.7±7.3y). Breath-hold PC cine MR images of the coronary sinus (CS) were acquired using a 1.5T MR scanner and 32 channel cardiac coils to assess blood flow of the CS at rest and during adenosine triphosphate (ATP) infusion. The CFR was calculated as CS blood flow during ATP infusion divided by that at rest. The CFR and LVEF were evaluated by MRI at baseline and at three months after starting therapy. RESULTS: Hemoglobin A1c (HbA1c) was significantly reduced in both groups (alogliptin, 7.2±0.6% to 6.6±0.5%, p=0.034; control, 6.9±0.4% to 6.4±0.3%, p=0.008). However, CFR and LVEF significantly improved only in the alogliptin group (alogliptin: CFR, 2.15±0.61 to 2.85±0.80, p=0.042; LVEF, 59.4±6.3% to 68.0±8.6%, p=0.03; control: CFR, 2.17±0.37 to 2.38±0.32, p=0.19; LVEF, 58.2±9.1 to 60.3±8.8%, p=0.61). The % increases in CFR and in LVEF positively correlated (R=0.47 by Spearman's correlation coefficient; p=0.036). CONCLUSION: The inhibition of DPP-4 by alogliptin improved CFR and LVEF evaluated by MRI in patients with type 2 DM and CAD and the improvement in CFR was associated with increased LV systolic function.