Impact of the downstream myocardial mass on values of coronary microvascular resistance.

The assessment of hyperemic microvascular resistance (HMR) may be dependent on the assessment location in the coronary artery and the amount of partial myocardial mass (PMM) distal to the assessment locations. The aim of this study was to investigate the differences in HMR values between the distal and proximal sites in the same coronary arteries as well as the relationship between HMR and PMM. Twenty-nine vessels from 26 patients who had undergone intracoronary physiological assessments including Doppler flow velocity at the distal third part and the proximal third part in the same vessels were assessed. The mean values of HMR and PMM at the distal sites were 2.08 ± 0.75 mmHg/cm/sec and 22.2 ± 10.4 g, respectively. At the proximal sites, the values of HMR and PMM were 1.19 ± 0.33 mmHg/cm/sec and 59.9 ± 18.3 g, respectively. All HMR values at the distal sites were significantly higher than those at the proximal sites (p < 0.001). Smaller PMM at the distal sites was significantly associated with higher HMR (r = -0.544, p = 0.002) and was the strongest factor affecting the HMR values (p = 0.009), while this relationship was not observed at the proximal sites (r = -0.262, p = 0.17). The impact of PMM on HMR was diminished at assessment locations where PMM was greater than 35 g. In conclusion, a small amount of downstream myocardial mass could be related to high HMR values. The assessment location around the proximal coronary artery with over 35 g of myocardium would be appropriate to assess HMR because it minimizes the influence of the assessment location.

Impact of Hemodialysis Duration on Coronary Artery Calcification Among Hemodialysis Patients Who Underwent Percutaneous Coronary Intervention.

Our study aimed to evaluate the prevalence and impact of coronary artery calcification (CAC) on hemodialysis (HD) patients with coronary artery disease (CAD) who underwent percutaneous coronary intervention (PCI). We enrolled 211 HD patients who underwent PCI (men: n = 155, age: 71 ± 1 0 years). Severe CAC was defined as calcification with an arc of 360° on intravascular ultrasound. Multivariate analysis was performed to determine the predictors of severe CAC. The impact of severe CAC on target lesion revascularization (TLR) was evaluated. Patients with severe CAC (46%) had a higher incidence of diabetes mellitus (DM) (79 vs 59%, P = .003) and longer HD duration (7.7 vs 3.4 years, P < .001) than those with non-severe CAC. Multivariate analysis demonstrated that DM, HD duration, and angiographic calcification were significant predictors for severe CAC (odds ratio 4.42, 1.13, and 6.62; P < .001, P < .001, and P < .001, respectively). After the median follow-up period of 580 days (interquartile range, 302-730 days), Kaplan-Meier curve analysis revealed that severe CAC was associated with an increased risk for TLR (χ2 12.7; P = .002). In HD patients with CAD after PCI, DM and HD duration were significant predictors for severe CAC. Furthermore, severe CAC was associated with an increased risk for TLR.

Angiographic flow velocity predicts lower limb outcomes after endovascular therapy: Application of the frame count method.

INTRODUCTION: Several factors related to lesion characteristics and endovascular therapy (EVT) procedures have been reported to affect primary patency after EVT. However, it is unknown why these factors were associated with primary patency. We hypothesized patency failure was related to poor blood flow in affected arteries. METHODS: This retrospective study included 131 consecutive patients who had received EVT with bare metal stents for peripheral artery disease caused by femoropopliteal artery lesions. Based on the tertile post-EVT flow velocity of the superficial femoral artery (SFA), patients were divided into high (n = 43), middle (n = 44), and low (n = 44) flow velocity groups. Flow velocity was measured using the frame count method. We measured incidence of major adverse limb events (MALE), composed of target lesion revascularization (TLR), non-TLR, and major amputation. RESULTS: At a median follow-up period of 22.7 months, MALE had occurred in 7 (16.3%), 10 (22.7%), and 29 (65.9%) of patients from the high, middle, and low SFA flow velocity groups, respectively (p < 0.001). Kaplan-Meier analysis showed incidence of MALE was significantly higher in the patients of low SFA flow velocity (log-rank test χ2 = 38.8, p < 0.001). Multivariate analysis found low SFA flow velocity to be an independent predictor for MALE (hazard ratio: 4.42; 95% CI: 2.27 to 8.60; p < 0.001) as was ankle-brachial index. CONCLUSION: Post-EVT SFA flow velocity for femoropopliteal artery lesions treated with bare metal stents is an independent predictor of limb patency. The frame count method for assessing arterial flow velocity is convenient and has potential for wide applications in EVT.

Eicosapentaenoic acid levels predict prognosis of peripheral artery disease caused by aortoiliac artery lesions.

BACKGROUND AND AIM: Eicosapentaenoic acid (EPA) has been reported to improve clinical outcome of high-risk atherosclerotic patients. We investigated whether endogenous EPA values predict prognosis of peripheral artery disease (PAD) patients. METHODS AND RESULTS: This retrospective study included 166 consecutive patients who had received endovascular therapy (EVT) for PAD caused by aortoiliac artery lesions. Patients were divided into 2 groups using median preoperative EPA value (57 µg/ml): LOW EPA (n = 83) and HIGH EPA (n = 83). We compared differences between the 2 groups in prevalence of major adverse limb events (MALE) which included target lesion revascularization (TLR), non-TLR, and major amputation, and major adverse events (MAE) which included MALE and all cause death. At a median follow-up period of 20 months, MALE had occurred in 24 LOW EPA patients (28.9%) and in 12 HIGH EPA patients (14.5%) (p = 0.04), and MAE had occurred in 41 LOW EPA patients (49.4%) and in 21 HIGH EPA patients (25.3%) (p < 0.01). Kaplan-Meier analysis showed prevalence of MALE and MAE was significantly higher in LOW EPA than in HIGH EPA (long-rank test χ2 = 8.5, p < 0.01, log-rank test χ2 = 13.2, p < 0.01, respectively). Multivariate Cox regression revealed preoperative EPA value < 57 µg/ml was an independent predictor for MALE (hazard ratio [HR]: 2.70; 95% CI: 1.35 to 5.4; p < 0.01) and MAE (HR: 2.86; 95% CI: 1.67 to 4.91; p < 0.01). CONCLUSIONS: Endogenous EPA value seems to be associated with risk of MALE and MAE after EVT in patients with PAD caused by aortoiliac artery lesions.

Clinical Outcomes after Endovascular Therapy Among Hemodialysis Patients with Peripheral Artery Disease Stratified by the Primary Kidney Disease.

OBJECTIVES: The objective of this study was to investigate the clinical characteristics of hemodialysis patients with peripheral artery disease (PAD) and the outcomes after endovascular therapy (EVT) in such patients stratified by the primary kidney disease. METHODS: This retrospective observational study evaluated 142 consecutive hemodialysis patients with symptomatic PAD who underwent EVT (men: n = 103, age: 74 ± 8 years). Patients were divided into 3 groups in accordance with the reason for hemodialysis: hypertensive nephrosclerosis (HTN [n = 26]), diabetic nephropathy (DN [n = 85]), and chronic glomerulosclerosis (CGN [n = 31]). The primary outcome was major adverse event(s) (MAEs), including target lesion revascularization, major amputation, and all-cause death. Clinical characteristics and outcomes were compared among the 3 groups. RESULTS: Patients with HTN were older (81 ± 6 years vs. 72 ± 8 years vs. 74 ± 8 years; P < 0.001) and had a shorter hemodialysis vintage (2.4 years vs. 6.8 years vs. 11.2 years; P < 0.001) than those with DN and CGN. Critical limb ischemia (CLI) affected 15 (58%) patients in the HTN group, 52 (61%) in the DN group, and 10 (32%) in the CGN group. Target lesion length was longer in patients with HTN than in those in the other groups (155 ± 101 mm vs. 108 ± 77 mm [DN] vs. 98 ± 76 mm [CGN]; P = 0.020). During a median follow-up period of 372 days (interquartile range, 198-730 days), Kaplan-Meier curve analysis revealed that HTN was associated with an increased risk for MAEs (χ2 11.6; P = 0.003). Furthermore, multivariate Cox regression analysis revealed that CLI, HTN, and B-type natriuretic peptide levels were independent predictors of MAE (hazard ratio 3.91, 2.88, and 1.00; P < 0.001, P < 0.001, and P = 0.001, respectively). CONCLUSIONS: Among hemodialysis patients with PAD, HTN was associated with an increased risk for MAEs after EVT.

Usefulness of Lipoprotein (a) for Predicting Outcomes After Percutaneous Coronary Intervention for Stable Angina Pectoris in Patients on Hemodialysis.

Serum lipoprotein (a) level is genetically determined and remains consistent during a person's life. Previous studies have reported that people with high lipoprotein (a) level are at a high risk of cardiac events. We investigated the association between lipoprotein (a) levels and clinical outcomes after percutaneous coronary intervention (PCI) for stable angina pectoris (SAP) in hemodialysis (HD) patients. Serum lipoprotein (a) levels were measured on admission in 410 consecutive HD patients who underwent successful PCI for SAP. Patients were divided into 2 groups: low and high group having lipoprotein (a) level <40 mg/dL (n = 297) and ≧40 mg/dL (n = 113) respectively. After PCI, the incidence of major adverse cardiac event (MACE) including cardiac death, nonfatal myocardial infarction, necessity of a new coronary revascularization procedure (coronary bypass surgery, repeat target lesion PCI, PCI for a new non-target lesion) was analyzed. At a median follow-up of 24 months (12 to 37 months), MACE occurred in 188 patients (45.6%). The rate of MACE rate was significantly higher in the high lipoprotein (a) group than in the low lipoprotein (a) group (59.2% vs 40.7%, long-rank test chi-square = 12.3; p < 0.001). Cox analysis showed that high lipoprotein (a) level (Hazard Ratio, 1.62; 95% Confidence Interval, 1.19 to 2.20; p = 0.002) was an independent predictor for MACE after PCI. In conclusion, high lipoprotein (a) level was associated with a higher incidence of MACE after PCI for SAP in HD patients.