Activation of the coagulation cascade and the role of paravalvular leak in the development of leaflet thrombosis following transcatheter aortic valve replacement

Aortic valve laceration following rotational atherectomy: a case report

Background

Iatrogenic aortic valve injury during cardiovascular catheterization interventions is extremely rare. Severe aortic regurgitation that ensues can be catastrophic and the management is typically with surgical valve replacement or repair. Percutaneous management of native pure aortic regurgitation is difficult due to anatomical challenges and the limitations of current transcatheter heart valve technology to anchor in the absence of leaflet or annular calcification.

Case Summary

An 82-year-old female underwent rotational atherectomy (RA) for a severely calcified stenosis of the left anterior descending artery. The patient was discharged well following placement of two drug eluting stents. She represented to hospital 7 days later with acute pulmonary oedema. Bedside transthoracic echocardiography demonstrated new, severe AR with preserved left ventricular size and function. Review of the prior percutaneous coronary intervention revealed significant trauma to the aortic valve during RA, with contrast seen refluxing into the LV during diastole, evolving throughout the procedure. Given the patient was not an operative candidate, an oversized transcatheter aortic valve was successfully implanted. In the post-operative setting, the patient suffered a stroke. Extensive hypoattenuated leaflet thickening (HALT) and thrombus was seen on dedicated 4D CT imaging. She made full neurological recovery and valve function returned to normal following a period of anticoagulation.

Conclusion

Although iatrogenic aortic valve laceration is rare, this case highlights several important learning points including the importance of good guide catheter support during RA; the feasibility of Transcatheter Aortic Valve Replacement for pure native AR; and the detection and management of HALT.

Clinical predictors and sequelae of computed tomography defined leaflet thrombosis following transcatheter aortic valve replacement at medium-term follow-up

BACKGROUND

The clinical predictors and sequelae of leaflet thrombosis (LT) following transcatheter aortic valve replacement (TAVR) is still unclear. Therefore, our aim was to determine the clinical predictors and sequelae at mid-term follow-up of computed tomography (CT)-defined LT following TAVR.

METHODS AND RESULTS

We performed a prospective evaluation with a 320-multislice CT following TAVR for the presence of LT, defined as hypo-attenuated leaflet thickening (HALT). Four-dimensional CT image-rendering was performed to determine the presence of reduced leaflet motion (RELM). 172 patients [89 (51.7%) male, mean age 82.8 ± 5.7 years] treated with commercially available TAVR device (Lotus 54%, CoreValve 32% and Sapien 3 14%) were included, with median CT-scan at 6.0 weeks post-TAVR. Prevalence of HALT was 14.0% (24 cases) and RELM was 9.8% (17 cases). On multivariate analysis, patients with HALT were less prescribed oral anticoagulation (OAC) (OR 9.9), received larger TAVR prostheses (OR 5.7) and higher rates of moderate-severe para-valvular regurgitation (PVR) (OR 16.3). There was no difference in clinical outcomes at a median follow-up of 2.3 years. Patients with RELM had significantly higher transvalvular gradients after discharge when compared to those without RELM.

CONCLUSIONS

Absence of OAC, large TAVR prostheses and moderate-severe PVR were predictors for LT. Transvalvular gradients were higher in patients that developed RELM but not HALT. Further studies are warranted to determine the long-term impact of LT on TAVR durability. Prevalence of different sub-types of CT-defined LT (HALT and RELM) and the clinical predictors of developing LT following TAVR. CT computed tomography, HALT hypo-attenuated leaflet thickening, LT leaflet thrombosis, RELM reduced leaflet motion, TAVR transcatheter aortic valve replacement.