Right Ventricle Dysfunction in Patients With Adult Cystic Fibrosis Enlisted for Lung Transplant

Right ventricle free wall longitudinal strain screening of lung transplant candidates

BACKGROUND

Lung transplant (LUTX) candidates have subclinical right ventricular (RV) dysfunction, which has not yet been assessed by speckle-tracking echocardiography (STE)-derived RV free-wall longitudinal strain (RVFWLS). To evaluate the prevalence of RV dysfunction by RVFWLS and its relationship with conventional RV echocardiographic indexes in LUTX candidates.

METHODS

In a single-center prospective observational cohort study, from January 2021 to March 2023 consecutive LUTX candidates underwent cardiac catheterization, radionuclide ventriculography, standard and STE. The diagnostic accuracy of RV ejection fraction by ventriculography (RVEF), tricuspid annular plane excursion (TAPSE), fractional area change (FAC), tricuspid peak annulus systolic velocity (S') versus RVFWS were computed.

RESULTS

Thirty-four patients (female, 41%) with a mean age of 48 [36-59] years old enlisted for pulmonary fibrosis (35%) and cystic fibrosis (30%) were included. At cardiac catheterization, only 7 (23%) had pulmonary hypertension. Around 15-25% presented right heart enlargement. Tricuspid regurgitation was present in 20 (60%) of the patients. Median RVFWLS was -20.1% [-22.5%--17%], being impaired (> -20%) in 16 (47%) of the patients. RVFWLS identified the highest percentage (47%) of RV dysfunction, compared to TAPSE (32%), S' (27%), FAC (26%), and ventriculography (15%), which had very low sensitivity for detecting RV dysfunction compared to RVFWLS.

CONCLUSIONS

In patients enlisted for LUTX, RV dysfunction assessed by STE-derived RVFWLS is highly prevalent. STE can detect RV dysfunction better than standard two-dimensional echocardiography and ventriculography. Further studies are urgently needed to define the clinical implications and the prognostic value of RV dysfunction measured with RVFWLS.

Longitudinal assessment of renal function after lung transplantation for cystic fibrosis: transition from post-operative acute kidney injury to acute kidney disease and chronic kidney failure

INTRODUCTION

The clinical trajectory of post-operative acute kidney injury (AKI) following lung transplantation for cystic fibrosis is unknown.

METHODS

Incidence and risk factors for post-operative AKI, acute kidney disease (AKD) and chronic kidney disease (CKD) were retrospectively analyzed in cystic fibrosis patients undergoing lung transplantation. Logistic regressions, Chi-square, Cuzick rank tests, and Cox-proportional hazard models were used.

RESULTS

Eighty-three patients were included. Creatinine peaked 3[2-4] days after transplantation, with 15(18%), 15(18%), and 20(24%) patients having post-operative AKI stages 1, 2, and 3, while 15(18%), 19(23%) and 10(12%) developed AKD stage 1, stage 2 and 3, respectively. Higher AKI stage was associated with worsening AKD (p = 0.009) and CKD (p = 0.015) stages. Of the 50 patients with AKI, 32(66%) transitioned to AKD stage > 0, and then 27 (56%) to CKD stage > 1. Female sex, extracorporeal membrane oxygenation support as a bridge to lung transplant and at the end of the surgery, the use of intraoperative blood components, and cold-ischemia time were associated with increased risk of post-operative AKI and AKD. Higher AKI stage prolonged invasive mechanical ventilation (p = 0.0001), ICU stay (p = 0.0001), and hospital stay (p = 0.0001), and increased the incidence of primary graft dysfunction (p = 0.035). Both AKI and AKD stages > 2 worsened long-term survival with risk ratios of 3.71 (1.34-10.2), p = 0.0131 and 2.65(1.02-6.87), p = 0.0443, respectively.

DISCUSSION

AKI is frequent in cystic fibrosis patients undergoing lung transplantation, it often evolves to AKD and to chronic kidney disease, thereby worsening short- and long-term outcomes.