Healthcare Resource Use, Baseline Characteristics, Clinical Outcomes and Survival Among Patients Undergoing SAVR vs TAVR in England

Study type
Protocol
Date of Approval
Study reference ID
20_167
Lay Summary

Aortic stenosis (AS) is one of the most common and serious valve disease problems. AS is a narrowing of the aortic valve opening, leading to an impaired outflow of blood from the heart. Traditionally open-heart surgery (Surgical Aortic Valve Replacement) would be the initial procedure where a new valve is placed in the heart, replacing the old valve. Alternatively, Transcatheter Aortic Valve Replacement (TAVR) is a procedure where a new valve is placed in the heart through a small tube (called a “catheter”) typically in the leg.

The Specialised Cardiac Improvement Programme (SCIP) states that due to the initial procedure, the TAVI procedure costs the NHS around double that of the SAVR procedure. However, recent evidence, suggests that TAVI procedures may be cost saving in the long term due to lower burden to healthcare resources including cardiac rehabilitation, re-admissions, length of stay and primary care activity.

This study aims to determine the size of the population group that underwent SAVR and TAVI in England. Further, we shall determine the health care resource use and costs and clinical outcomes associated with these groups of patients in a comparative manner.

This study will be able to provide an in-depth understanding of the post-surgical pathway in England considering the risk of adverse health outcomes among each group of patients. This will trigger further research and inform health policy, treatment and clinical management options, especially targeting patients with risk factors to enable better outcomes in turn reducing costs and healthcare resource usage associated with AS.

Technical Summary

Aortic stenosis (AS) causes impaired outflow of blood from the heart. The increased cardiac workload leads to left ventricular hypertrophy and heart failure.

Surgical aortic valve replacement (SAVR) with an artificial prosthesis is the conventional treatment for patients with severe AS. Transcatheter aortic valve implantation (TAVI) is a less invasive alternative treatment to SAVR for treating aortic stenosis, avoiding the need for sternotomy and cardiopulmonary bypass.

The Specialised Cardiac Improvement Programme (SCIP) states that due to the initial procedure, the TAVI procedure costs the NHS around double that of the SAVR procedure. However recent evidence suggests that TAVI procedures may be cost saving in the long term due to lower healthcare resource utilisation including cardiac rehabilitation, re-admissions, length of stay and primary care activity.

This will be a descriptive study which aims to determine the long-term cost savings for TAVI procedures compared to SAVR procedures. This will be achieved by quantifying the healthcare resource utilisation of a SAVR cohort of patients compared to a TAVI cohort including secondary care activity such as re-admissions, length of stay and primary care activity. The study design has been chosen as this is appropriate for data extracted from healthcare datasets that already have data collected retrospectively. CPRD-HES linked dataset has been chosen due to the availability of good quality data for procedures, demographics, costs, complications, readmissions and resource use.

We shall describe the cohort in terms of a risk score based on a proxy of the Society of Thoracic Surgery (STS) risk score. Health care resource usage for the cohort will be calculated and reported for readmissions, outpatient appointments, length of stay, and primary care appointments. Outcomes and the incidence of procedure-related complications in the two chosen and matched cohorts. will be described as total, means, medians, percentage, or rates as appropriate.

Health Outcomes to be Measured

Prevalence of TAVR; Prevalence of SAVR; Prevalence of co-morbidities and risk factors in the cohort (CAD, CABG, PCI, MI, Heart failure, Arrhythmia and AFIB); Demographics (Mean and median age on inclusion, percent males, total, mean and median follow-up and geographical region); Complications post-surgery(Major bleed, acute kidney disease, Coronary-artery obstruction, Major vascular complications, cardiac perforation, stroke, cardiogenic perforations, cardiogenic shock, atrial fibrillation); Healthcare resource outcomes (procedures in secondary care, total appointments and cost in primary care, outpatient appointments, A&E attendances, inpatient admissions, inpatient length of stay, inpatient HRG tariffs, prior hospitalisation); Clinical outcomes (mortality, Major Adverse Cardiac Event, heart failure)

Collaborators

Jennifer Davidson - Chief Investigator - Health iQ Ltd ( UK ) t/a CorEvitas
Jennifer Davidson - Corresponding Applicant - Health iQ Ltd ( UK ) t/a CorEvitas
Archie Farrer - Collaborator - Health iQ Ltd ( UK ) t/a CorEvitas
Christopher Spencer - Collaborator - Health iQ Ltd ( UK ) t/a CorEvitas
Eva Maria Fuchs - Collaborator - Health iQ Ltd ( UK ) t/a CorEvitas
Gulsah Akin Unal - Collaborator - Health iQ Ltd ( UK ) t/a CorEvitas
Yasir Hassan - Collaborator - Health iQ Ltd ( UK ) t/a CorEvitas

Former Collaborators

Gulsah Akin Unal - Collaborator - Health iQ Ltd ( UK ) t/a CorEvitas

Linkages

HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Patient Level Index of Multiple Deprivation