Sinus arrest following angioplasty and stenting for superior vena cava syndrome

Superior vena cava (SVC) syndrome is a complication resulting from long-term residence of leads or in-dwelling catheters at the SVC to right atrial (RA) junction. SVC syndrome management is complicated by variable responses to anticoagulation therapies and technically challenging interventional procedures, such as balloon dilatation or stent placement at the SVC-RA junction to relieve blood-flow obstruction. Potential complications resulting from angioplasty/stenting for SVC syndrome are serious and include stent migration, major bleeding, and embolism. Bradyarrhythmias have not been reported. We describe a case of balloon angioplasty and stenting for SVC syndrome in a dialysis patient that resulted in sinus arrest. The complication developed within hours of angioplasty/stenting of her chronic, non-thrombotic SVC obstruction. We highlight the management approach to this patient and discuss potential mechanisms underlying the complication.

Abstract P57: The Baseline Characteristics Predictive of a Poor Procedural Response to Balloon Aortic Valvuloplasty Among a Cohort of High–Surgical Risk Patients with Aortic Stenosis

Background: Balloon aortic valvuloplasty (BAV) for high-surgical risk patients with severe aortic stenosis (AS) has been used as a palliative therapy, a bridge to surgical aortic valve replacement (AVR) or to transcatheter aortic valve implantation (TAVI). Poor procedural response, including poor improvements in the aortic valve area (AVA) and the mean aortic valve pressure gradient (AVPG) immediately following BAV have been demonstrated to predict mortality following BAV. Whether any baseline characteristics can predict a poor procedural response to BAV has not been assessed.

Methods: We retrospectively reviewed the medical records of 74 consecutive, AS patients who underwent BAV. Patient's baseline demographics, comorbid medical conditions, medications, laboratory results and echocardiographic findings were correlated with changes in the AVA and the mean AVPG immediately post-BAV.

Results: The mean age was 80 ± 4 years, the mean Society of Thoracic Surgeons Surgical Risk Score (STS) was 7.73 ± 6.26 and the mean logistic EuroSCORE was 23.8 ± 15.4. There was 1 periprocedural death, 16 (21.6%) patients were bridged to AVR or to TAVI and 58 (78.3%) of the patients received palliative or definitive therapy. The mean AVA increased from 0.72 ± 0.24 cm 2 to 1.12 ± 0.42 cm 2 and the mean AVPG decreased from 42.09 ± 16.54 mmHg to 24.41 ± 10.86 mmHg. Overall, no baseline characteristics were statistically significant predictors of poor AVA improvements following BAV (Table 1). Patient's age < 80 years old was the only significant, independent predictor of poor AVPG reduction post-BAV compared to patient's > 80 years of age (Table 1).

Conclusion: Prior to BAV, age < 80 years of age was the only characteristic predictive of a poor procedural response. All other baseline characteristics including patient demographics, pre-existing medical conditions, active medications and laboratory values were poor predictors of the procedural response to BAV therapy.

The influence of low (81 mg) versus high (325 mg) doses of ASA on the incidence of sirolimus-eluting stent thrombosis

BACKGROUND

Conflicting opinion exists regarding the optimal dose of acetyl salicylic acid (ASA) to be given after percutaneous coronary intervention (PCI) with drug-eluting stents (DES). We sought to evaluate the influence of ASA dose on the incidence of unexplained subacute and late stent thrombosis in the era of DES.

METHODS

We performed a retrospective analysis of the incidence of subacute and late stent thrombosis in our patient population over a 2-year period. The analysis was limited to patients being discharged and maintained on a daily ASA dose of either 81 mg or 325 mg and having received at least 1 sirolimus-eluting stent.

RESULTS

During the study period, 1,093 patients (1,807 separate PCI procedures) met the inclusion criteria. The incidence of unexplained subacute and late stent thrombosis was 1.1% in the study population (12 out of 1,093 patients). When considering the total number of individual procedures performed on the study population during the study period (1,807 procedures), the incidence of unexplained subacute or late stent thrombosis was 0.7%. Six were subacute and 6 were late thrombosis. No significant difference was observed in the incidence of stent thrombosis between the 2 ASA dose groups. Seven patients had stent thrombosis in the 81 mg group (1.2% of 583 patients), while 5 had thrombosis in the 325 mg group (1% of 510 patients); p = 0.727.

CONCLUSION

In conclusion, we found no significant difference in the incidence of unexplained subacute or late stent thrombosis with the use of an 81 mg versus 325 mg dose of aspirin post-PCI with sirolimus-eluting stents.