Vascular Medicine最新文献

Introduction: Patients with chronic limb-threatening ischemia (CLTI) have high mortality rates after revascularization. Risk stratification for short-term outcomes is challenging. We aimed to develop machine-learning models to rank predictive variables for 30-day and 90-day all-cause mortality after peripheral vascular intervention (PVI).

Methods: Patients undergoing PVI for CLTI in the Medicare-linked Vascular Quality Initiative were included. Sixty-six preprocedural variables were included. Random survival forest (RSF) models were constructed for 30-day and 90-day all-cause mortality in the training sample and evaluated in the testing sample. Predictive variables were ranked based on the frequency that they caused branch splitting nearest the root node by importance-weighted relative importance plots. Model performance was assessed by the Brier score, continuous ranked probability score, out-of-bag error rate, and Harrell's C-index.

Results: A total of 10,114 patients were included. The crude mortality rate was 4.4% at 30 days and 10.6% at 90 days. RSF models commonly identified stage 5 chronic kidney disease (CKD), dementia, congestive heart failure (CHF), age, urgent procedures, and need for assisted care as the most predictive variables. For both models, eight of the top 10 variables were either medical comorbidities or functional status variables. Models showed good discrimination (C-statistic 0.72 and 0.73) and calibration (Brier score 0.03 and 0.10).

Conclusion: RSF models for 30-day and 90-day all-cause mortality commonly identified CKD, dementia, CHF, need for assisted care at home, urgent procedures, and age as the most predictive variables as critical factors in CLTI. Results may help guide individualized risk-benefit treatment conversations regarding PVI.

Background: For primary Raynaud phenomenon (PRP), an otherwise unexplained vasospastic disposition is assumed. To test the hypothesis of an additional involvement of distinct ultrastructural microvascular alterations, we compared the nailfold capillary pattern of patients with PRP and healthy controls.

Methods: A total of 120 patients with PRP (with a median duration of vasospastic symptoms of 60 [IQR: 3-120] months) were compared against 125 controls. In both groups, nailfold capillaroscopy was performed to record the presence of dilatations, capillary edema, tortuous capillaries, ramifications, hemorrhages, and reduced capillary density and to determine a semiquantitative rating score. Further, the capacity of finger skin rewarming was investigated by performing infrared thermography in combination with cold provocation.

Results: Unspecific morphologic alterations were found in both, PRP, such as controls, whereby the risk for PRP was four times as high in the presence of capillary dilations (CI: 2.3-7.6) and five times as high if capillary density was reduced (CI: 1.9-13.5). Capillary density correlated with thermoregulatory capacity in both hands in the PRP group, but not in controls. In addition, a negative correlation between the microangiopathy score and the percentage degree of rewarming in both hands was found for patients with PRP only.

Conclusion: We found specific differences within the microvascular architecture between patients with PRP and controls. As a conclusion, PRP may not be an entirely benign vasospastic phenomenon, but might be associated with subtle microcirculatory vasculopathy. In addition, we suggest that the implementation of a scoring system might serve as guidance in the diagnostic process at least of patients with long-standing PRP.

Background: Anatomy is critical in risk stratification and therapeutic decision making in coronary disease. The relationship between anatomy and outcomes is not well described in PAD. We sought to develop an angiographic core lab within the VOYAGER-PAD trial. The current report describes the methods of creating this core lab, its study population, and baseline anatomic variables. Methods: Patients undergoing lower-extremity revascularization for symptomatic PAD were randomized in VOYAGER-PAD. The median follow up was 2.25 years. Events were adjudicated by a blinded Clinical Endpoint Committee. Angiograms were collected from study participants; those with available angiograms formed this core lab cohort. Angiograms were scored for anatomic and flow characteristics by trained reviewers blinded to treatment. Ten percent of angiograms were evaluated independently by two reviewers; inter-rater agreement was assessed. Clinical characteristics and the treatment effect of rivaroxaban were compared between the core lab cohort and noncore lab participants. Anatomic data by segment were analyzed. Results: Of 6564 participants randomized in VOYAGER-PAD, catheter-based angiograms from 1666 patients were obtained for this core lab. Anatomic and flow characteristics were collected across 16 anatomic segments by 15 reviewers. Concordance between reviewers for anatomic and flow variables across segments was 90.5% (24,417/26,968). Clinical characteristics were similar between patients in the core lab and those not included. The effect of rivaroxaban on the primary efficacy and safety outcomes was also similar. Conclusions: The VOYAGER-PAD angiographic core lab provides an opportunity to correlate PAD anatomy with independently adjudicated outcomes and provide insights into therapy for PAD. (ClinicalTrials.gov Identifier: NCT02504216).