Impact of Hospital Volume on Long-Term Outcomes After Endovascular Therapy for Peripheral Artery Disease.

PURPOSE: To investigate the association between annual hospital volume of endovascular therapy (EVT) and long-term outcomes in patients with lower-extremity peripheral artery disease (PAD). MATERIALS AND METHODS: We identified patients who underwent percutaneous endovascular transluminal angioplasty and thrombectomy of the extremities or percutaneous endovascular removal in the Japanese Diagnosis Procedure Combination inpatient database from April 2014 to March 2020 linked to the Survey of Medical Institutions data. A generalized linear model analysis was performed to assess 12-month amputation, all-cause death, composite outcome (amputation and death), and readmission. We also analyzed length of hospital stay and total health care costs during the first hospitalization. RESULTS: Among 127 486 eligible patients, 31 579, 31 913, 31 999, and 31 995 were in the first (1-27 cases/year), second (28-44 cases), third (45-67 cases), and fourth (68-289 cases) quartiles, respectively. There were no significant differences in 12-month amputation among the second (odds ratio [OR], 0.97; 95% confidence interval [CI], 0.90-1.04), third (OR, 1.00; 95% CI, 0.93-1.07), and fourth (OR, 1.00; 95% CI, 0.93-1.07) quartile volumes compared with the first quartile. Significant differences were observed in 12-month death (OR for fourth quartile with reference to the first quartile, 0.71; 95% CI, 0.65-0.76), composite outcome (OR, 0.84; 95% CI, 0.80-0.89), and readmission (OR, 1.05; 95% CI, 1.02-1.09). CONCLUSIONS: We found that the annual hospital volume of EVT was not associated with decreased 12-month amputation in patients with lower-extremity PAD. In contrast, all-cause death and composite outcome were significantly decreased in hospitals with the highest volume. CLINICAL IMPACT: The association between hospital volume of endovascular therapy and long-term adverse clinical outcomes remains unclear. The present analyses showed no significant differences in 12-month amputation rates among the hospital volumes, whereas higher-volume quartiles were significantly associated with decreased 12-month all-cause death rates and composite outcome. There was also a positive association in the length of stay between the first quartile volume and the others, while no significant difference in total health care costs among the quartiles was observed. Further investigations are needed, including insights into operator volume and procedural characteristics, to clarify the relationship between hospital volume and long-term adverse outcomes.

Amputation After Endovascular Therapy With and Without Intravascular Ultrasound Guidance: A Nationwide Propensity Score-Matched Study.

BACKGROUND: Intravascular ultrasound (IVUS) provides precise intravascular information during endovascular therapy (EVT). However, the clinical efficacy of IVUS in patients who undergo EVT remains unknown. The present study aimed to determine whether the use of IVUS-guided EVT is associated with better clinical outcomes in a real-world setting. METHODS: Using the Japanese Diagnosis Procedure Combination administrative inpatient database from April 2014 to March 2019, we identified patients diagnosed with atherosclerosis of arteries of extremities and underwent EVT (percutaneous endovascular transluminal angioplasty and thrombectomy for extremities or percutaneous endovascular removal). Propensity score matching analysis was performed to compare outcomes between the patients who underwent IVUS on the same day as the first EVT intervention (IVUS group) and the others (non-IVUS group). The primary outcome was major and minor amputation for extremities within 12 months of the first EVT procedure. Secondary outcomes were bypass surgery, stent grafting, reintervention, all-cause death, readmission, and total hospitalization costs within 12 months of the first EVT procedure. RESULTS: Among 85 649 eligible patients, 50 925 (59.5%) were IVUS group. After propensity score matching, the IVUS group had significantly lower incidence of 12-month amputation compared with the non-IVUS group (6.9% in the IVUS group versus 9.3% in the non-IVUS group; hazard ratio, 0.80 [95% CI, 0.72-0.89]). Compared with the non-IVUS group, the IVUS group showed a lower risk of bypass surgery and stent grafting and decreased total hospitalization costs, while a higher risk of reintervention and readmission. No significant differences in all-cause death were found between the 2 groups. CONCLUSIONS: In this retrospective study, IVUS-guided EVT was associated with a lower amputation risk than non-IVUS-guided EVT. Our findings should be interpreted carefully because of the limitations of an observational study using administrative data. Further studies are warranted to confirm whether IVUS-guided EVT leads to decreased amputations.

Characteristics and short-term outcomes of outpatient and inpatient cardiac catheterizations: A descriptive study using a nationwide claim database in Japan.

BACKGROUND: Most previous studies on outpatient cardiac catheterization have been conducted in Western countries, but Japanese studies are rare. We aimed to describe patient characteristics and short-term clinical outcomes of outpatient cardiac catheterization compared to those of inpatient cardiac catheterization in Japan. METHODS: We conducted a retrospective cohort study using data from the JMDC Claims Database. We identified all adult patients aged ≥18 years who underwent cardiac catheterization between April 2012 and October 2021. We investigated patient characteristics and clinical outcomes (i.e. all-cause mortality, stroke, acute kidney injury, bleeding, vascular complications, percutaneous coronary intervention, and total healthcare costs) within 2, 7, and 30 days between patients who underwent outpatient cardiac catheterization (outpatient group) and those who underwent inpatient cardiac catheterization (inpatient group). RESULTS: Of the 37,002 eligible patients (57.6 % <60 years old, and 80.2 % male), 1853 (5.01 %) underwent outpatient cardiac catheterization. The outpatient group was more likely to be male, have more comorbidities, and be performed at non-university hospitals than the inpatient group. The proportion of patients who underwent right heart catheterization and imaging was lower in the outpatient group. There were no significant differences in 7-day major complications between the two groups (all-cause mortality, 0.0 % versus 0.0 %, p = 0.57; acute kidney injury, 0.0 % versus 0.1 %, p = 0.10, bleeding, 0.5 % versus 0.9 %, p = 0.052; vascular complication, 0.0 % versus 0.1 %, p = 0.23, respectively). The 30-day total healthcare costs were lower in the outpatient group than in the inpatient group (mean 3212 US dollars versus 3955 US dollars, p = 0.003). CONCLUSIONS: Approximately 5 % of cardiac catheterizations were performed in an outpatient setting. Given the low adverse event risk observed in this study, it may be a reasonable option to widen outpatient cardiac catheterization to include potential populations in Japan, warranting further studies.