Evaluating care of patients who have undergone percutaneous coronary interventions: the British Cardiovascular Intervention Society database

Introduction: There is a need to study the level of percutaneous coronary intervention (PCI) care in the UK to promote improvements in care for all patients with cardiovascular disease. The aim of this thesis was to utilise contemporary population-based data to perform a number of investigations and answer several important questions regarding the level of care provided to patients who have undergone PCI in the UK on the basis of outcomes including survival. Methods: A linked population-based study using the prospectively collected British Cardiovascular Intervention Society (BCIS) registry of patients who have undergone PCI in the UK since January 2005. Three main analyses were performed and for each part; a literature review, analysis (descriptive statistics, comparisons, adjusted associations and survival), multi-level modelling and fit for purpose imputation were conducted. Results: In the first analysis, 5,065 patients with unprotected left main stem disease (UPLMS) were studied. More than half of patients treated with PCI to the UPLMS presented acutely, their early and late mortality were significantly worse than that for elective patients. Cardiogenic shock was common in ST elevation myocardial infarction (STEMI) and associated with a 1 in 2 risk of early mortality. In acute patients, radial access was associated with improved early outcomes. In the second analysis, 10,827 patients with UPLMS were studied. The number of acute patients with UPLMS PCI increased over the years with stable early and late mortality rates. In the third analysis, 98,637 patients with STEMI were studied. The survival of primary PCI patients was worse than that of facilitated and rescue mainly because majority of the procedures were performed after more than two hours from the onset of symptoms. Old age, cardiogenic shock, more than two hours delay before intervention, inter-hospital transfer and being already in a cardiac centre were independent predictors of worse survival in primary interventions. Conclusions: The novel prospective data used in this thesis have provided the opportunity to gain more knowledge and understanding of the quality of care provided to patients following PCI which represents a step forward in the assessment and improvement of cardiovascular health services in the UK

Demographic Characteristics and Status of Vaccinated Individuals with a History of COVID-19 Infection Pre- or Post-Vaccination: A Descriptive Study of a Nationally Representative Sample in Saudi Arabia

Background: Saudi Arabia expedited the approval of some COVID-19 vaccines and launched mass vaccination campaigns. The aim of this study was to describe the demographics of vaccinated COVID-19 cases and compare the mortality rates of COVID-19 cases who were infected post-vaccination in Saudi Arabia. Methods: This was a retrospective cohort study. We retrieved data for COVID-19 cases who were infected pre- or post-vaccination and had received at least one injection of the Oxford–AstraZeneca or Pfizer–BioNTech vaccine from 4 December 2020 to 15 October 2021. Results: The number of patients who were infected and had received at least one dose of a COVID-19 vaccine was 281,744. Approximately 45% of subjects were infected post-vaccination, and 75% of subjects had received the Pfizer–BioNTech vaccine. Only 0.342% of the patients who were infected post-vaccination died, and 447 patients were admitted to ICUs. Most of the patients who were infected with COVID-19 post-vaccination and were admitted to ICUs (69.84%) had received only one dose of the vaccine (p < 0.0001). The mean time to infection for patients who had received one and two doses of the Oxford–AstraZeneca vaccine were 27 and 8 days longer than their counterparts who had received one and two doses of Pfizer–BioNTech vaccine, respectively. No difference in the odds of mortality between the Pfizer–BioNTech and Oxford–AstraZeneca vaccines was found (OR = 1.121, 95% CI = [0.907–1.386], p-value = 0.291). Patients who had received two doses of the vaccine had significantly lower odds of mortality compared to those who had received one dose (p < 0.0001). Conclusions: Vaccines are vital in combating the COVID-19 pandemic. The results of this study show no difference between the Pfizer–BioNTech and Oxford–AstraZeneca vaccines in the rate of mortality. However, the number of vaccine doses was significantly associated with a lower risk of mortality. Future studies should examine the effectiveness of different COVID-19 vaccines using real-world data and more robust designs

Launching COVID-19 vaccination in Saudi Arabia: Lessons learned, and the way forward

This article is made available for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic.The Severe Acute Respiratory Syndrome Coronavirus 2 (SARSCoV- 2) emerged in Wuhan City, China. The SARS-CoV-2 crossed borders and quickly transformed into a "Public health emergency of international concern". Countries around the globe are in the race to achieve herd immunity. We describe the steps taken by Saudi Arabia to achieve this goal