Bipolar radiofrequency ablation delivered from coronary veins and adjacent endocardium for treatment of refractory left ventricular summit arrhythmias.

BACKGROUND: Radiofrequency catheter ablation (RFCA) of premature ventricular complexes (PVC) and ventricular tachycardia (VT) can be an effective method of treatment. However, when arrhythmia originates from the left ventricular summit (LVS), an ablation performed with conventional unipolar energy sources can be challenging and may require alternative approaches. Bipolar RFCA from coronary veins and an adjacent endocardium in cases of refractory PVC/VT has not yet been studied. METHODS: We retrospectively analysed cases of consecutive patients who underwent bipolar ablation in whom conventional unipolar ablation of LVS PVC/VT and antiarrhythmic drugs failed to abolish arrhythmia. Bipolar RFCA was delivered from the earliest PVC/VT activation located in the coronary venous circulation and opposite LV endocardial sites. RESULTS: A total number of 4 patients (1 female, age 55 ± 10 years) underwent bipolar ablation of LVS from coronary veins and an adjacent endocardium. Bipolar RFCA led to acute elimination of PVC/VT in all patients. A mean bipolar RFCA time was 244 ± 15 s. There were no complications during procedures and all antiarrhythmic drugs were discontinued. A follow-up lasted 15 ± 4 months; there was no VT recurrence and the mean 83 ± 27 % PVC burden reduction (24250 ± 1372 vs. 3000 ± 3600 PVC/d; p = 0.0228) was achieved. All patients remained symptom-free. CONCLUSIONS: Bipolar RFCA from coronary veins and an opposite endocardium can be used for safe and successful treatment of PVC/VT originating from a deep LV summit.

Percutaneous recanalisation of chronically occluded coronary arteries with the CrossBoss/Stingray system: first experience (report of three cases).

BACKGROUND AND AIM: Percutaneous coronary interventions (PCI) within chronically occluded coronary arteries remain challenging procedures with a lower success rate compared to classic PCI. However, over the last years we have witnessed many technological advances in the treatment of chronic total occlusion (CTO) including new wires, retrograde approach, subintimal tracking and re-entry technique, all underlying which the current success rate of up to 95% in dedicated centres. Subintimal space wire penetration is no longer a problem that would require terminating the procedure. It is now a desired part of hybrid CTO approach involving both antegrade and retrograde crossing and re-entry. The new device which facilitates controlled dissection and true lumen re-entry is the Boston Scientific Coronary CTO Crossing System consisting of a CrossBoss micro-catheter and Stingray balloon and dedicated wire. METHODS: On October 29th and 30th, 2014, percutaneous coronary recanalisation using the CrossBoss/Stingray system was performed in 3 men aged 63-75, with symptoms of stable CCS class II/III angina, without prior myocardial infarction in the area of CTO artery supply and with preserved myocardial contractility. Each patient underwent at least one previous unsuccesful antegrade/retrograde CTO recanalisation procedure. The J-CTO score was 3-4. RESULTS: The procedure was successful in all 3 patients: 2 right coronary arteries and 1 left anterior descending artery were opened. In all 3 cases, both the CrossBoss catheter and the Stingray re-entry system were used. Two to three drug eluting stents were implanted in each patient, with the total length of 62-106 mm and final TIMI 3 flow. The mean procedure time was 141 min (130-150 min), mean fluoroscopy time was 53 min (48-56 min), absorbed dose was 4772 mGy (4098-5633 mGy), dose area product was 565,208 cGy × cm² (535,109-590,266 cGy × cm²), and the mean contrast volume was 343 mL (320-350 mL). No procedure-related complications were note except for an asymptomatic increase in high-sensitivity troponin T level up to 157 ng/mL (reference range 0-14 ng/mL) in 1 patient. CONCLUSIONS: The Boston Scientific Coronary CTO Crossing System is a useful device for percutaneous recanalisation of chronically occluded coronary arteries. It helps to achieve procedural success in more complex cases within relatively short crossing times and with a limited amount of the contrast agent and X-ray dose.