3326Infective endocarditis after transcatheter aortic valve implantation: findings from a UK nationwide linkage study

Introduction

Infective endocarditis (IE) is a potentially fatal complication of prosthetic valve replacement and increasing use of transcatheter aortic valve implantation (TAVI) has resulted in a new elderly and frail population at increased risk of IE. The incidence of IE after TAVI and factors that influence the risk and subsequent outcome are relatively unknown.

Purpose

To describe the incidence, predictors, echocardiographic findings, microbiology and clinical outcomes of IE following TAVI in the United Kingdom (UK).

Methods

Patients who underwent TAVI between Jan 1 2007 and Dec 31 2016 were identified from the UK TAVI database held by the National Institute for Cardiovascular Outcomes Research. For this cohort, all hospital admissions with a primary diagnosis of IE were identified by linkage with the NHS Hospital Episode Statistics Admitted Patient Care database, or by contact with regional TAVI centres. Additional information concerning clinical presentation, imaging findings, microbiology, management and patient outcome were obtained where possible from the treating physician.

Results

A total of 16,014 patients underwent TAVI, of whom 157 developed IE over a median follow-up of 23.8 (IQR 7.8–52.4) months - an overall incidence of 0.98% (0.53% at one year post-TAVI). The mean age of patients with IE was 79.2±7.8 years, and 69% were male. The median time to IE following TAVI was 10.0 (IQR 4.0–22.3) months.

On multivariate analysis, IE was significantly more common in men (HR 2.05, 95% CI 1.35–3.11, p=0.001) and in patients receiving mechanically-expandable (HR 2.15, 95% CI 1.16–4.01, p=0.015) or balloon-expandable valves (HR 1.60, 95% CI 1.01–2.52, p=0.045) compared to self-expanding valves. IE was also more common in those with an aortic valve peak gradient following TAVI deployment greater than median (HR 1.81, 95% CI 1.23–2.67, p=0.003).

The most common presenting symptom was fever (present in 67.1%). The most frequent causal organisms were enterococci (25.9%), followed by oral streptococci (16.4%) and Staphylococcus aureus (11.8%). Transoesophageal echocardiography demonstrated vegetations in 72.5% of patients, most commonly on the TAVI valve leaflets (58.8%). Only 8.24% of patients underwent surgical valve intervention.

Survival rates at hospital discharge and one year follow up were 61.4% and 54.4%, respectively. Specific factors associated with one-year mortality were cardiogenic shock (HR 4.6, 95% CI 2.1–10.3, p=0.0002), septic shock (HR 3.4, 95% CI 1.4–8.3, p=0.006) and stroke (HR 4.9, 95% CI 1.46–16.7, p=0.01).

Conclusions

The incidence of IE one year after TAVI was 0.53% and greater risk was associated with male sex, mechanically-expandable and balloon-expandable valves, and elevated post-deployment valve gradient. Enterococci were the most common causative organism. Overall survival at one year was 54.4%, with adverse outcome predicted by cardiogenic shock, septic shock or stroke.

Genetic screening of newborn in Australia. Results for 1981

Since screening of newborn infants for phenylketonuria (PKU) by the Guthrie bacterial inhibition assay was established in the 1960s, 3 017 703 infants have been tested in Australia. Two hundred and fifty-one cases of PKU (0.83/10 000) and six cases of the variant forms of malignant hyperphenylalaninaemia (MHPA) (0.02/10 000) have been detected. In 1981, 11 infants with PKU were detected. Screening for congenital hypothyroidism was carried out in seven States, and 66 new cases were detected in 1981 (2.13/10 000). In Adelaide, 154 310 infants have been tested for galactosaemia and a total of seven cases have now been detected (0.45/10 000). In New South Wales, 35 955 infants have been tested for cystic fibrosis of the pancreas, and 17 cases were found (4.73/10 000).

Genetic screening of newborn in Australia: results for 1980

Since screening of newborn infants for phenylketonuria (PKU) by Guthrie bacterial inhibition assay was established in the 1960s, 2779 790 infants have been tested in Australia. Two hundred and forty cases of PKU (rate: 1/11 582) and six cases of the variant forms of malignant hyperphenylalaninaemia (MHPA) (rate: 1/463 298) have been detected. In 1980, 18 infants with PKU were detected. Screening for congenital hypothyroidism was carried out in six centres, and 40 new cases were detected in 1980.

Genetic screening of newborn in Australia: results for 1979

Since screening of newborn infants for phenylketonuria (PKU) by Guthrie bacterial inhibition assay was established in the 1960s, 2 556 498 infants have been tested in Australia. Two hundred and twenty-two cases of PKU, and five cases of the variant forms of malignant hyperphenylalaninaemia (MHPA) have been found over this period, an incidence of 1/11 516 for PKU, and 1/511 300 for MHPA. In 1979, 18 infants with PKU and one with MHPA were detected. Screening for congenital hypothyroidism was carried out in four centres, and 28 new cases were detected in 1979 (an incidence of 1/5746).

Genetic screening of the newborn in Australia. Results for 1978

Since screening of newborn infants for phenylketonuria (PKU) by Guthrie bacterial inhibition assay was established in the 1960s. 2 334 679 infants have been tested in Australia, and 208 cases of PKU detected (an incidence of 1/11 224). In 1978, 21 infants with PKU were detected. Screening for hypothyroidism was carried out in three States, and 29 cases of congenital hypothyroidism were detected in 1978 (an incidence of 1/5894).