Design and rationale of the efficacy of spinal cord stimulation in patients with refractory angina pectoris (SCRAP) trial.

BACKGROUND: The use of spinal cord stimulation (SCS) in patients with refractory angina pectoris (RAP) is still under debate. Studies up to date have shown a positive effect with an improvement in quality of life. However, no double blinded randomized controlled trials have been performed. HYPOTHESIS & METHODS: The objective of this trial is to investigate if high density SCS leads to a significant reduction in the amount of myocardial ischemia in patients with RAP. Eligible patients must meet the criteria for RAP, have proven ischemia and a positive transcutaneous electrical nerve stimulator treadmill test. Patients who meet the inclusion criteria will receive an implanted spinal cord stimulator. Patients receive 6 months of high density SCS and 6 months of no stimulation using a cross-over design. The order of the treatment options is determined using randomization. The primary endpoint is the effect of SCS measured by the change in percentage of myocardial ischemia using myocardial perfusion positron emission tomography scan. Key secondary endpoints are patient related outcome measures, major cardiac adverse events and safety endpoints. The follow-up period is 1 year for the primary and key secondary endpoints. RESULTS: The SCRAP trial began enrollment on December 21, 2021 and is set to complete the primary assessments in June 2025. To date, January 2, 2023, 18 patients have been enrolled in the study and 3 patients have completed the 1-year follow-up. CONCLUSIONS: The SCRAP trial is an investigator-initiated, single-center, double-blind, placebo-controlled, and cross-over randomized controlled trial investigating the efficacy of SCS in patients with RAP. (ClinicalTrials. gov Identifier: NCT04915157).

Long-term efficacy and safety of spinal cord stimulation in patients with refractory angina pectoris.

Background: The number of patients with refractory angina pectoris (RAP), associated with poor quality of life, has been steadily increasing. Spinal cord stimulation (SCS) is a last resort treatment option leading to significant improvement in quality of life over a one year follow-up. The aim of this prospective, single-centre, observational cohort study is to determine the long-term efficacy and safety of SCS in patients with RAP. Methods: All patients with RAP who received a spinal cord stimulator from the period July 2010 up to November 2019 were included. In May 2022 all patients were screened for long-term follow-up. If the patient was alive the Seattle Angina (SAQ) and RAND-36 questionnaire were completed and if the patient had passed away cause of death was determined. The primary endpoint is the change in SAQ summary score at long-term follow-up compared to baseline. Results: From July 2010 up to November 2019 132 patients received a spinal cord stimulator due to RAP. The mean follow-up period was 65.2 ± 32.8 months. Seventy-one patients completed the SAQ at baseline and long-term follow-up. The SAQ SS showed an improvement of 24.32U (95% confidence interval [CI]: 18.71 - 29.93; p < 0.001). Conclusions: The main findings of the study show that long-term SCS in patients with RAP leads to significant improvement in quality of life, significant reduction in angina frequency, significantly less use of short-acting nitrates and a low risk of spinal cord stimulator related complications over a mean follow-up period of 65.2 ± 32.8 months.

Improvement of angiographic and clinical outcomes of percutaneous coronary intervention for chronic total occlusion after implementation of a dedicated team: a single-centre experience.

INTRODUCTION: In a Dutch heart centre, a dedicated chronic total occlusion (CTO) team was implemented in June 2017. The aim of this study was to the evaluate treatment success and clinical outcomes before and after this implementation. METHODS: A total of 662 patients who underwent percutaneous coronary intervention (PCI) for a CTO between January 2013 and June 2020 were included and divided into pre- and post-CTO team groups. The primary endpoint was the angiographic success rate of CTO-PCI. Secondary endpoints included angiographic success stratified by complexity using the J­CTO score and the following clinical outcomes: in-hospital complications and myocardial infarction, target vessel revascularisation, all-cause mortality, quality of life (QoL) and major adverse cardiac events (MACE) at 30-day and 1­year follow-up. RESULTS: Compared with the pre-CTO team group, the success rate in the post-CTO team group was higher after the first attempt (81.4% vs 62.7%; p < 0.001) and final attempt (86.7% vs 73.8%; p = 0.001). This was mainly driven by higher success rates for difficult and very difficult CTO lesions according to the J­CTO score. The MACE rate at 1 year was lower in the post-CTO team group than in the pre-CTO team group (6.4% vs 16.0%; p < 0.01), while it was comparable at 30-day follow-up (0.1% vs 1.7%; p = 0.74). Angina symptoms were significantly reduced at 30-day and 1­year follow-up, and QoL scores were higher after 1 year. CONCLUSION: This study demonstrated higher success rates of CTO-PCI and improved clinical outcomes and QoL at 1­year follow-up after implementation of a dedicated CTO team using the hybrid algorithm.

Coronary physiology before and after chronic total occlusion treatment: what does it tell us?

Studies performed in the last two decades demonstrate that after successful percutaneous coronary intervention (PCI) of a chronically occluded coronary artery, the physiology of the chronic total occlusion (CTO) vessel and dependent microvasculature does not normalise immediately but improves significantly over time. Generally, there is an increase in fractional flow reserve (FFR) in the CTO artery, a decrease in collateral blood supply and an increase in FFR in the donor artery accompanied by an increase in blood flow and decrease in microvascular resistance in the myocardium supplied by the CTO vessel. Analogous to these physiological changes, positive remodelling of the distal CTO artery also occurs over time, and intravascular imaging can be helpful for analysing distal vessel parameters. Follow-up coronary angiography with physiological measurements after several weeks to months can be helpful and informative in a subset of patients in order to decide upon the necessity for treatment of residual coronary artery stenosis in the vessel distal to the CTO or in the contralateral donor artery, as well as in deciding whether stent optimisation is indicated. We suggest that such physiological guidance of CTO procedures avoids unnecessary overtreatment during the initial procedure, guides interventions at follow-up, and improves our understanding of what PCI in CTO means.

Improvement in quality of life and angina pectoris: 1-year follow-up of patients with refractory angina pectoris and spinal cord stimulation.

AIMS: Spinal cord stimulation (SCS) is a treatment for patients with refractory angina pectoris (RAP) who remain symptomatic despite optimal medical therapy and without revascularisation options. Previous studies have shown that SCS improves the quality of life in this patient group and reduces the severity of the angina pectoris. The aim of this prospective, single-arm observational study is to show this effect in a single-centre cohort using a multidisciplinary team approach to the selection process, with a follow-up period of 1 year. METHODS AND RESULTS: Between July 2010 and March 2017, 87 patients with RAP referred to our centre received SCS. The Seattle Angina Questionnaire (SAQ) and RAND 36-Item Health Survey (RAND-36) were completed at baseline, prior to implantation, and 1 year post-implantation. After 1 year of follow-up there was a statistically significant decrease in the frequency of angina pectoris attacks from more than 4 times a day to 1-2 times a week (p < 0.001). The SAQ showed statistically significant improvement in four of the five dimensions: physical limitation (p < 0.001), angina frequency (p < 0.001), angina stability (p < 0.001) and quality of life (p < 0.001). The RAND-36 showed statistically significant improvement in all nine dimensions: physical functioning (p = 0.001), role/physical (p < 0.001), social functioning (p = 0.03), role/emotional (p < 0.05), bodily pain (p < 0.001), general health (p < 0.001), vitality (p < 0.001), mental health (p = 0.02) and health change (p < 0.001). CONCLUSION: This study showed a significant improvement in quality of life and reduction of angina pectoris severity after 1 year of follow-up in patients treated with SCS for RAP.

Circadian and weekly variation and the influence of environmental variables in acute myocardial infarction.

OBJECTIVES: The aim of our study was to investigate the circadian and weekly variation and assess the influence of environmental variables on the occurrence of acute myocardial infarction (AMI). METHODS: Our study population consisted of 2983 consecutive patients admitted with AMI between January 2006 and May 2008. Data were abstracted from hospital records and partially from an electronic database. In patients with a known time of onset of AMI, circadian variation was analysed. In all patients, weekly variation of onset of AMI was analysed. Information on daily mean temperature, sunny hours, rainy hours, maximal humidity and mean atmospheric pressure was obtained from the KNMI database and the influence of these environmental variables on the incidence of AMI was analysed. RESULTS AND CONCLUSION: Incidence of AMI shows a circadian pattern with an increase in occurrence during daylight. AMI occurs equally on each day of the week and no relation was found between environmental variables and the occurrence of AMI.