Ionizing radiation exposure in complex percutaneous coronary intervention: Defining local diagnostic reference levels in the catheterization laboratory.

INTRODUCTION AND OBJECTIVES: Concerns regarding the consequences of ionizing radiation (IR) have been increasing in the field of interventional cardiology (IC). There is little information on reported national and local radiation diagnostic reference levels (DRLs) in catheterization laboratories in Portugal. This study was designed to assess the IR dose exposure during complex percutaneous coronary intervention (PCI), and to set the respective DRLs and future achievable doses (ADs). METHODS: This was a retrospective cohort study which took place between 2019 and 2020, including patients who underwent complex PCI. Complex PCI was defined as all procedures that encompass treatment of chronic total occlusions (CTO) or left main coronary artery. DRLs were defined as the 75th percentile of the distribution of the median values of air kerma area product (PKA) and cumulative air kerma (Ka,r). ADs were set at the 50th percentile of the study dose distribution. Multivariate analysis was performed using linear regression to identify predictors significantly associated with radiation dose (Ka,r). RESULTS: A total of 242 patients were included in the analysis. Most patients underwent a CTO procedure (146, 60.3%). Patients were aged 67.9±11.2 years and mostly male (81.4%). DRLs were set in Ka,r (3012 mGy) and PKA (162 Gy cm2) for complex PCI. ADs were also set in Ka,r (1917 mGy) and PKA (101 Gy cm2). Independent predictors of Ka,r with a positive correlation were PKA (0.893, p<0.001), fluoroscopy time (0.520, p<0.001) and PCI time (0.521, p<0.001). CONCLUSIONS: This study reports the results of IR in complex PCI. DRLs were set for IR dose exposure measured in Ka,r (3012 mGy) and PKA (162 Gy cm2). ADs, values to be achieved in future assessment, were set to Ka,r (1917 mGy) and PKA (101 Gy cm2).

Clinical results of percutaneous coronary intervention in chronic total occlusions of the right coronary artery.

INTRODUCTION AND OBJECTIVES: Coronary chronic total occlusions (CTOs) of the right coronary artery (RCA) are a relatively common finding in the context of coronary angiography. However, the benefit of revascularization remains controversial. METHODS: A single-center retrospective cohort analysis prospectively collected outcomes of CTO patients undergoing percutaneous coronary intervention (PCI) in 2019 and 2020. Patients were divided into two groups according to the CTO vessel treated (left coronary artery [LCA]-CTO or RCA-CTO). The primary outcome was defined as the recurrence of angina and/or heart failure (HF) symptoms and secondary outcomes were myocardial infarction (MI) and all-cause mortality. RESULTS: A total of 177 patients (82.5% male) were included in the analysis, with a mean age of 65±11 years. The primary outcome occurred in 28 (16.6%) patients and was significantly more frequent in RCA-CTO patients (19, 24.7%, p=0.010) in a mean follow-up of 18 months. This was mainly driven by recurrence of HF symptoms (12, 15.6%, p=0.013). Treated RCA-CTO was an independent predictor of the primary outcome (p=0.019, HR 2.66, 95% CI 1.17-6.05). MI and mortality rates were no different between groups (RCA-CTO with 1.3%, p=0.361 and 2.6%, p=0.673, respectively, on survival analysis). Left ventricular ejection fraction was an independent predictor of mortality (p=0.041, HR 0.93, 95% CI 0.87-0.99). CONCLUSIONS: Revascularization of CTO lesions by PCI was associated with low rates of symptom recurrence, and clinical outcomes showed no differences regardless of which artery was treated. Recanalization of RCA-CTO was less beneficial in reducing the recurrence of HF symptoms.

A report on a survey among Portuguese Association of Interventional Cardiology associates regarding ionizing radiation protection practices in national interventional cath-labs.

INTRODUCTION AND OBJECTIVES: Concerns surrounding the consequences of ionizing radiation (IR) have increased in interventional cardiology (IC). Despite this, the ever-growing complexity of diseases as well as procedures can lead to greater exposure to radiation. The aim of this survey, led by Portuguese Association of Interventional Cardiology (APIC), was to evaluate the level of awareness and current practices on IR protection among its members. METHODS: An online survey was emailed to all APIC members, between August and November 2021. The questionnaire consisted of 50 questions focusing on knowledge and measures of IR protection in the catheterization laboratory. Results were analyzed using descriptive statistics. RESULTS: From a response rate of 46.9%, the study obtained a total sample of 159 responses (156 selected for analysis). Most survey respondents (66.0%) were unaware of the radiation exposure category, and only 60.4% reported systematically using a dosimeter. A large majority (90.4%) employed techniques to minimize exposure to radiation. All participants used personal protective equipment, despite eyewear protection only being used frequently by 49.2% of main operators. Ceiling suspended shields and table protectors were often used. Only two-thirds were familiar with the legally established limit on radiation doses for workers or the dose that should trigger patient follow-up. Most of the survey respondents had a non-certified training in IR procedures and only 32.0% had attended their yearly occupational health consultation. CONCLUSIONS: Safety methods and protective equipment are largely adopted among interventional cardiologists, who have shown some IR awareness. Despite this, there is room for improvement, especially concerning the use of eyewear protection, monitoring, and certification.

Clinical outcomes of percutaneous coronary intervention in chronic total occlusion in patients with type 2 diabetes mellitus.

INTRODUCTION AND OBJECTIVES: Coronary chronic total occlusions (CTOs) are relatively common findings in patients with type 2 diabetes mellitus (T2DM). However, the indication for percutaneous coronary intervention (PCI) and its clinical benefit in these patients remain controversial. METHODS: A single-center retrospective cohort study with prospectively collected outcomes was carried out with CTO patients undergoing PCI in 2019 and 2020. Patients were divided into two groups according to previous T2DM diagnosis (T2DM and non-T2DM). The primary outcome was recurrence of angina and/or heart failure symptoms and secondary outcomes were myocardial infarction and all-cause mortality. RESULTS: A total of 177 patients (82.5% male) were included in the analysis, with a mean age of 65±11 years. The primary outcome (total symptom recurrence) occurred in 16.6% of the sample, with no difference between groups (non-T2DM 13.6% vs. T2DM 21.2%, p=0.194) in a two-year follow-up. Angina recurrence was significantly more frequent in T2DM patients (15.2%, p=0.043). The presence of T2DM was not an independent predictor of symptom recurrence (p=0.429, HR 1.37, 95% CI 0.62-2.98). Myocardial infarction and all-cause mortality were also not different between groups (T2DM 1.5%, p=0.786 and 4.5%, p=0.352, respectively, on survival analysis). Independent predictors of all-cause mortality were left ventricular function and creatine clearance (p=0.039, HR 0.92, 95% CI 0.85-0.99 and p=0.013, HR 0.96, 95% CI 0.93-0.99, respectively). CONCLUSIONS: T2DM did not influence outcomes in CTO patients undergoing PCI, and its presence should not be a limiting factor in deciding on CTO revascularization.