AF ablation — structured written assessment

SAQ 1 (10 marks)

Practice scenario. A 57-year-old man has symptomatic paroxysmal AF that has recurred despite flecainide. He wants to stay in sinus rhythm and is referred for catheter ablation. His CHA2DS2-VA score is 2, and he takes rivaroxaban.^[1][2]

1. Give the ESC 2024 and ACC/AHA 2023 rows that support ablation for him, with class and level. (2)^[1][2]
2. What is the procedural endpoint of pulmonary vein isolation, and how is it verified? (2)^[3]
3. How should his anticoagulation be managed before and during the procedure? Give the ESC 2024 and ACC/AHA 2023 rows. (2)^[1][2]
4. How long should OAC continue afterwards, and what decides the long-term plan? Give the ESC 2024 and ACC/AHA 2023 rows. (2)^[1][2]
5. Name four complications from ACC/AHA 2023 Table 26 with their frequencies. (2)^[2]

Model answers — SAQ 1

1. ESC 2024: catheter ablation is recommended in paroxysmal or persistent AF resistant or intolerant to antiarrhythmic drug therapy, to reduce symptoms, recurrence and progression of AF (Class I, Level A) (1 mark).^[1] ACC/AHA 2023: in symptomatic AF in whom antiarrhythmic drugs have been ineffective, contraindicated, not tolerated or not preferred, and continued rhythm control is desired, ablation is useful to improve symptoms (COR 1, LOE A) (1 mark).^[2]
2. Electrical disconnection between the pulmonary veins and the left atrium (1 mark).^[3] It can be verified by showing no wavefront propagation from the LA to the PV (entrance block) and/or from the PV to the LA (exit block) (1 mark).^[3]
3. ESC 2024: OAC is recommended at least 3 weeks before catheter-based ablation in AF patients at elevated thromboembolic risk (Class I, Level C), and uninterrupted OAC during the procedure (Class I, Level A), both to prevent peri-procedural ischaemic stroke and thromboembolism (1 mark).^[1] ACC/AHA 2023: on a DOAC, ablation should be performed with either continuous or minimally interrupted oral anticoagulation (COR 1, LOE A) (1 mark).^[2]
4. ESC 2024: OAC is recommended for at least 2 months after ablation in all patients, irrespective of rhythm outcome or CHA2DS2-VA score (Class I, Level C), and continuing OAC after ablation is recommended according to the CHA2DS2-VA score and not the perceived success of the ablation (Class I, Level C) (1 mark).^[1] ACC/AHA 2023: OAC should be continued for at least 3 months with a longer duration determined by underlying risk (COR 1, LOE B-NR), and longer-term OAC should be dictated by stroke risk, eg, CHA2DS2-VASc score of 2 or more (COR 1, LOE B-NR) (1 mark).^[2]
5. Any four of: cardiac perforation with tamponade 0.4%–1.5%; LA–oesophageal fistula 0.2%; stroke or TIA 0.1%–1.0%; pulmonary vein stenosis 0.1%–0.8%; phrenic nerve paralysis 0.2%–0.4%; vascular access complications 1%–7%; vascular access complications requiring surgery 0.1%–0.3%; death 0.1%–0.4%; pneumonia 0.4%–1.0% (half a mark each).^[2]

SAQ 2 (10 marks)

Practice scenario. A 63-year-old man presents with a new diagnosis of both heart failure with reduced ejection fraction (HFrEF; LVEF 30%) and symptomatic persistent AF; the AF began about 7 months ago and has been continuous since (high-burden AF). He is on guideline-directed medical therapy. His clinicians judge that there is a clear cause–effect relationship: the AF is causing the heart failure. His electrophysiologist judges that he is an appropriate candidate with a reasonable expectation of benefit from ablation.^[2][4]

1. Give the two ACC/AHA 2023 rows from its Section 9.2 (Management of AF in Patients With HF) that recommend rhythm control or catheter ablation for him, with COR and LOE. (2)^[2]
2. Give the 2026 ESC heart failure row on ablation and the criteria its footnote requires. (2)^[4]
3. Describe the population and results of CASTLE-AF as the 2024 consensus reports them. (2)^[3]
4. List four characteristics the 2024 consensus associates with LVEF recovery after ablation. (2)^[3]
5. After a successful ablation, his CHA2DS2-VASc score is 1 (heart failure). Summarise the consensus advice on stopping anticoagulation by stroke-risk group. (2)^[3][1]

Model answers — SAQ 2

1. With a new diagnosis of HFrEF and AF, arrhythmia-induced cardiomyopathy should be suspected, and an early and aggressive approach to AF rhythm control is recommended (COR 1, LOE B-NR) (1 mark).^[2] In appropriate patients with AF and HFrEF on GDMT with reasonable expectation of procedural benefit, catheter ablation is beneficial to improve symptoms, quality of life, ventricular function and cardiovascular outcomes (COR 1, LOE A) (1 mark).^[2]
2. Catheter ablation for AF should be considered in selected patients with symptomatic AF and HFrEF to improve quality of life and reduce the risk of HF hospitalisation or death (Class IIa, Level C) (1 mark).^[4] All of: high-burden AF; under 1 year of continuous persistent AF; a clear cause–effect relationship between AF and HF (1 mark).^[4]
3. Paroxysmal or persistent AF with HF (NYHA class II or above, LVEF below 35%) and an implantable cardioverter-defibrillator, unresponsive, intolerant or unwilling to take AADs; randomised to ablation or medical rate or rhythm control (1 mark).^[3] Fewer patients in the ablation group had death from any cause or hospitalisation for worsening HF at 3.2 years (28.5% vs 44.6%; HR 0.62; P = 0.007), and mortality was also significantly lower with ablation (13.4% vs 25.0%; HR 0.53; P = 0.01) (1 mark).^[3]
4. Any four of the nine consensus Table 7 characteristics: lower NYHA class (I and II) at presentation; non-ischaemic HF aetiology; persistent AF; narrow QRS (≤120 ms); less atrial fibrosis (extent of atrial fibrosis is inversely correlated with LVEF response); absence of ventricular fibrosis in non-ischaemic cardiomyopathy with persistent AF; improvement in functional status and/or LVEF after cardioversion; no severe atrial dilatation (LAVI ≤50 mL/m²); AF diagnosed with or before the HF (half a mark each).^[3]
5. Low risk (CHA2DS2-VASc 0 in men, 1 in women): anticoagulation should be discontinued 2 months after ablation regardless of the ablation outcome; intermediate risk (1 in men, 2 in women), which is his group: discontinuation may be considered 12 months after ablation in the absence of clinical symptoms or ECG-documented AF recurrence, with commitment to long-term rhythm monitoring as a proposed prerequisite (1 mark).^[3] Higher risk (2 or more in men, 3 or more in women): anticoagulation should not be discontinued (1 mark).^[3]