Complications During Cardiovascular Interventions: Management and Prevention

Complications During Cardiovascular Interventions: Management and Prevention Helmut Pürerfellner, MD Public Hospital Elisabethinen Academic Teaching Hospital Linz, Austria

Atrial Tachycardia/Atypical left atrial flutter after catheter ablation of AFib 5-20% of atrial tachycardia after catheter ablation of AFib Several types: - macro-reentry without gap - macro-reentry with gap in a linear line - micro-reentry due to non-contiguous lines (circumferential or linear lines) - PV arrhythmias with specific LA conduction - focal atrial arrhythmias - right atrial isthmus dependent typical flutter (cave p wave)

Identification of left atrial flutter/tachycardia after AFib ablation P wave - p wave morphology - absence or presence of isoelectric interval Entrainment, post-pacing interval 3-D- activation mapping Ablation - gap related: focal ablation - broad isthmus: linear ablation

Narrow slow conducting isthmus dependent left atrial reentry (Shah et al, JCE 2006;17:508-515)

ECG, mapping and ablation

Entrainment

ECG, mapping and ablation

Case Report Pat. A.S., 68 years, male AFib history since 9 months (first diagnosis) ECV 03/05 successful (NSR), AFib recurred shortly after and persisted over next months Hypertensive heart disease, NIDDM, COPD Symptoms: Dyspnea on exertion, Palpitations Drug history: Bisoprolol

Case report cont d Admission to hospital 07/05 Echo: LA 49mm, LVH (Septum13mm), LVF normal CAG 07/05: no significant stenosis Scheduled for AFib ablation

Case report cont d RF ablation 10/05 (Carto Merge): Circumferential PV isolation of all 4 PVs (including ostial RF delivery LSPV and RSPV), roofline (in between RSPV and LSPV); SR restored at the end of the procedure, AFib recurred before discharge (no ECV) Unsatisfying clinical course over the next 3 months despite drug treatment (propafenon, bisoprolol) and ECV 12/05

Case report cont d Extensive Reablation 01/06 (Carto Merge): circumferential atrial reisolation of the PVs (LIPV reconnected), inferior line (including CS ablation), roof line, local ablation LAA to roof, local ablation septal, right atrial lesions (CT) restoring SR (including ibutilide i.v.) Unremarkable course over the next 9 months in stable SR

Case report cont d Regular follow up 04/06: ECG: SR, 64/min Echo: LA 42mm, LVF normal Stress test: moderate exercise capacity Drug Rx: Bisoprolol, ACEI Chest X-ray:

Chest X ray: 27-Apr-2006

Chest X Ray: 16-Jan-2006

Chest X Ray: 19-Jan-2006

Case report cont d Regular follow up 10/06: ECG: SR Lung function: normal, no paradox diaphragmatic motion, no signs for restrictive/obstructive ventilation dysfunction, blood gas normal Chest Xray:

Chest X Ray: 09-Oct-2006

Direct energy delivery (dog model) Bunch et al, JCE 2005;16:1318-25

Tissue temperatures after ablation Bunch et al, JCE 2005;16:1318-25

Direct nerve heating Bunch et al, JCE 2005;16:1318-25

PNI Histology Bunch et al, JCE 2005;16:1318-25 Thermal injury including edema, coagulation, homogenization of cytoplasmatic contents, fading/smearing of nuclear chromatin

PNI proposed mechanisms Direct heat transfer from ablation site to the PN (PN retaining heat due to insulatory properties) Electromagnetic field generated at the catheter tip Generation of a resonance current around the heart Demyelineation injury due to hypothermia (cryoablation, cooling)

Human Anatomy RSPV - Right PN: mean distance 1,5-4,5mm SVC - Right PN: mean distance 0-2,3mm

Anatomic relationship between the right/left phrenic nerve and the heart

Phrenic Nerve Injury (PNI) after Atrial Fibrillation Catheter Ablation Sacher et al, JACC 2006;47:2498-503 Multicenter Study in 3755 pts (1997-2004) 18 pts (0,48%, 9 male, 54±10 years) with PNI (16 right, 2 left) PVI (n=15), WACA (n=3) Right PNI: RSPV (n=12) or SVC disconnection (n=4) Left PNI: Ablation at LAA Variety of catheters (4-mm, 8-mm, irrigated tip) and energy sources (RF, ultrasound)

PNI after Atrial Fibrillation Catheter Ablation cont d Immediate clinical features: dyspnea, cough, hiccup ± diaphragmatic elevation (n=9) Late diagnosis: dyspnea (n=7), routine radiographic evaluation (n=2) 4 pts (22%) asymptomatic

PNI after Atrial Fibrillation Catheter Ablation cont d Complete recovery: n=12 (66%) Early recovery within 24 hours (n=3), late recovery after 4±5 months (range 1-12) (n=9) Persistent PNI: n=6 (34%) including partial recovery (n=3) Mean follow up 36±33 months

PNI Prevention Strategies Appreciation of critical structures: RSPV ostium (inferoanterior part), SVC (posteroseptal part), LAA (proximal roof) Ablation of RSPV and SVC as proximal as possible (venoatrial junction) Avoid ablation in case of diaphragmatic contraction during pacing with maximal output at critical sites Early fluoroscopic recognition during RF delivery with regard to diaphragmatic excursion (rapid recovery of PN function in 56%)

Complications During Cardiovascular Interventions: Management and Prevention Helmut Pürerfellner, MD Public Hospital Elisabethinen Academic Teaching Hospital Linz, Austria

Case report Pat. R.H., 30 years, male History of persistent AF since 06/01( lone AF ) ECV 08/01, recurrences in follow up Drugs: Betablocker, Sotalol

Case report cont d Ostial segmental PVI 11/01 (RSPV, LSPV, LIPV) Ostial segmental PVI 12/01 (RSPV) due to early recurrences

Case report cont d 01/02 unscheduled hospital readmission due to persistent cough starting 2 weeks after last procedure Spiral-CT: low-grade PV stenosis (<30%) both in LIPV/RSPV 02/02: scheduled follow up Spiral-CT: RSPV 60-70%, LIPV 30%; Still palpitations on sotalol (self terminating), dyspnea on exertion

Case report cont d 05/02: Admission on Lung Department due to hemoptysis since 2 weeks, suspected PE lung scan: MRI + CT scanning:

Imaging techniques Pürerfellner et al, Am J Cardiol, 2004;93:1428-1431

Case report cont d Diagnosis: Symptomatic subtotal PV stenosis RSPV Tx: RSPV Dilatation/StentingStenting: Herculinck stent (9mm diameter, 18mm length) Tx: Warfarin, Betablockade ( persisting AFib)

Case report cont d 07/02 routine readmission CT: adequate stent perfusion, distal vessel narrowing TEE: normal flow pattern RSPV Lung scan: reduced perfusion right upper lobe ECG: persisting AFib

Case report cont d 10/02: routine readmission, good clinical condition ECG: NSR (Flecainide, Metoprolol) TEE/CT/MRI: normal flow pattern RSPV Lung scan: almost normalized perfusion right uppper lobe

Case report cont d 05/03: routine readmission, good clinical condition Results unchanged, drugs withdrawn 10/06: good clinical condition, no arrhythmias since 2003, drug free

Tips and Tricks Integration of data from a variety of techniques (CT/MRI, venography) Electroanatomic mapping with virtual tubes including a virtual ring over three points defined at the ostial perimeter (±guidance of a circular catheter) 3-D mapping systems incorporating 3-D CT/MRI images

Determining Factors Abandonment of in-vein focal ablation Ablation at /outside PV orifice Reduction in ablation temperature and amount of energy Use of ICE Increased operator experience Jais (2002): up to 20% PV stenosis in centers <50 procedures/year (European Registry)

Open questions PV Ablation: energy setting, energy source, ablation technique PV Intervention: stent design, antithrombotic drug regimen (restenosis!) Asymptomatic single PV stenosis: conservative vs interventional strategy (RCT) Pulmonary hypertension...

Atrial-esophageal fistula Pappone et al, Circulation 2004;109:2724-2726

Periesophageal vagal injury after ablation Shah et al, JACC 2005;46:327-330