Gold Coast CPD · Cardiology / EP · ~29 min · Otter transcript

AF ablation seminar: inside the PFA lab — energy sources, CT planning, ICE-guided access & who to refer early

A Gold Coast electrophysiologist walks GPs through what actually happens in the ablation lab: why the pulmonary veins matter, how radiofrequency, cryo and pulsed field ablation differ, the “not a free lunch” trade-offs of PFA, and the patients he wants to see sooner.

Theme: cranberry · Recorded 10 March 2026 (AEST) · Canonical: allcpd.drkotha.com/af-ablation-seminar

Speaker: Cardiac electrophysiologist, Gold Coast — introduced on the transcript as “John Mulay” (surname unclear on ASR). Says he trained at the Cleveland Clinic (USA); works mainly at John Flynn and Pindara; heart rhythm disturbances and cardiac devices.
Host: Ramsay event host (name not captured) — round-table, case-based evening; event title garbled on ASR. Sponsor thanked: Edwards Lifesciences.
Session context: Otter title Atrial Fibrillation Ablation Seminar · id 09iEFKUehWSmqxWwh7SMY9plnis · ~29 min (1759 s). Speakers labelled Unknown Speaker / Speaker 1–3; almost all content is Speaker 1 (the EP). Slides were shown but not captured.

Already covered elsewhere on allcpd: the general PFA-era overview is at AF ablation overview, the referral-focused update at AF ablation update 2026, and mechanisms and drug management at AF in general practice. This post focuses on what this speaker emphasised: the lab workflow, energy-source trade-offs and his patient-selection rules.

Key messages for GPs

Refer symptomatic paroxysmal AF early. The speaker’s slide: catheter ablation is now “safe, effective and efficient” with pulsed field ablation (PFA); offer it sooner rather than later.
Long-standing AF is harder to fix. After 5, 10, 15 years the atrium stretches and remodels and non-pulmonary-vein triggers appear.
Start anticoagulation before referral when the CHA₂DS₂-VASc score warrants it (he asked for a DOAC at a score of 2 — see anticoagulation).
PFA is non-thermal — no heat or cold spread, so the classic oesophageal and phrenic nerve injuries of thermal ablation are, in his account, avoided. But it has its own specific issues (haemolysis, vagal pauses, coronary spasm).
The lab is faster: ~4-second applications, ~16–20 s of energy per vein; he says he can now do seven cases in a row in one lab.

Key takeaway

The best candidate, in his words, is a young, fit, symptomatic patient with paroxysmal AF — e.g. someone with repeated ED visits for IV flecainide and cardioversion. The poorest candidate has had continuous AF for >3 years with a left atrium about double normal size; for them it is rate control and anticoagulation.

The “AF epidemic” in an EP clinic

The speaker set the scene with his own workload. More Australians are over 65 than at any time in history, and the prevalence of AF climbs steeply with age — as best the transcript captures it, roughly 1 in 20 around age 60 and 1 in 5 around age 80 (numbers partly garbled on ASR). He said nine out of ten of his new case referrals are AF; the rest are SVT, PVCs and similar. He called it “almost an epidemic”.

Device work adds to the load: pacemakers and defibrillators need checks every 12 months for battery and leads, pacing clinics can run to ~50 patients a day, and with remote monitoring he receives daily alerts — prolonged AF episodes, shocks for VT/VF, low-battery warnings. His group is bringing on a fellow and a general cardiologist with a pacing interest to help.

Why the pulmonary veins?

He retold the origin story: a French team in Bordeaux (the ASR renders the lead name as “Michelle has Seguin” — the Haïssaguerre group) noticed during an EP study that ectopic beats from inside a pulmonary vein were initiating AF. Isolating one vein helped only until another vein started firing; over repeated procedures they found that all four veins can trigger AF at different times.

He quoted the pulmonary veins as the trigger site in about 95–98% of patients.
Occasionally the superior vena cava or crista terminalis (right atrium) act as triggers.
So isolating all four veins at the first operation is “the low-hanging fruit” — an empirical approach that he says fixes most patients.
Early operators ablated inside the veins, causing circumferential scar and pulmonary vein stenosis. The lesson: ablate at the ostium/antrum where the vein joins the atrium.

Schematic only. The speaker: PV triggers in ~95–98% of patients; occasionally SVC or crista terminalis. Isolating all four veins first is the “low-hanging fruit”.

Three energy sources compared

He described the three technologies currently available. The first two are thermal — and that, he stressed, is what causes “friendly fire” to bystander organs in the chest.

1. Radiofrequency (RF) — the point-by-point hot catheter

Irrigated catheter heats tissue to ~70 °C (as stated); the tip senses contact pressure, so the operator knows whether it is floating, touching gently or pressing firmly.
Lesions are small, so you draw a “dot-to-dot” ring around each vein — up to 3–3½ hours on a big day.
Risks he listed: perforation if pressure is too high; steam pop if the tip overheats; oesophageal ulceration; phrenic nerve palsy; post-procedure pericarditis/inflammation; PV stenosis if ablating inside the vein; thrombus on catheters (heparin throughout).
Usually two transseptal punctures — one for the ablation catheter, one for a 20-electrode circular mapping catheter to prove isolation.

2. Cryoballoon — freezing at the vein opening

Single transseptal puncture; a balloon seals the vein ostium and freezes circumferentially (~−70 °C, as stated), with a mapping catheter through the central lumen.
About a 4-minute freeze per vein, often repeated 2–3 times. Awake patients may get a severe “ice-cream headache”; oesophageal injury has been described.

3. Pulsed field ablation (PFA) — non-thermal electroporation

Very short bursts of high-voltage DC energy (pulse trains over ~4 seconds) open pores in myocyte membranes; the cells then die (apoptosis).
He described the frequency/voltage as specific to cardiac myocytes, with no change in local temperature — hence no oesophageal ulcer/fistula or phrenic nerve palsy in his account.
No subsequent PV stenosis, as he described it.

Summary of the speaker’s comparison. Figures (temperatures, durations, throughput) are as stated in the talk and captured by Otter; they describe his practice, not universal benchmarks.

PFA: “not a free lunch”

The speaker was careful not to oversell. “Everything in medicine has a cost, a price and a possible side effect.” The PFA-specific issues he plans for:

Issue	What he described	How he mitigates
Haemolysis	Energy delivered while floating in the blood pool damages red cells; with many applications (he cited >70) patients can get dark urine/haematuria-type discolouration.	Good tissue contact; limit the number of applications.
Vagal reflex	Ablating near the left upper pulmonary vein (vagal ganglia) can cause a long sinus pause (~15 s quoted).	Pre-treats with atropine (dose captured as 1,200 micrograms on ASR — specialist lab protocol) and keeps a pacing catheter in the heart.
Coronary spasm	PFA over a coronary artery — e.g. a cavotricuspid isthmus line for typical flutter — can cause vasospasm with ST elevation.	He uses PFA only for pulmonary vein isolation, not flutter lines or near coronaries (others pre-treat with IV nitroglycerin).
Hybrid catheters	A Medtronic catheter (called “360” on the transcript) can deliver PFA and RF.	In RF mode, all the thermal cautions return.

A healthy scepticism

“You never want to be the first person to use a new technology or the last person to use an old one.” He waited roughly six months, watched colleagues’ outcomes on the coast and read the literature before adopting PFA. He mentioned a colleague with nearly 300 PFA cases over ~2 years, and the John Flynn lab doing roughly 620 EP studies and ablations a year (figure as captured).

He also noted that many PFA catheter iterations exist internationally (he mentioned several in China) but only two were available in Australia at the time of the talk.

His lab workflow: CT, flower & basket, ICE

Cardiac CT for everyone, weeks ahead. Pulmonary vein anatomy varies widely — he has seen a patient with seven veins and another with only two. He builds a 3D model and pre-selects catheter size (e.g. a 31 mm configuration).
Two catheter shapes. The PFA catheter he uses (the Farapulse-style device; ASR “Farah pulse”) enters flat, then opens into a flower (five petals × four platinum electrodes) pressed against the antrum and rotated between applications, and a basket that sits in the vein ostium “like an egg in a cup”. A typical four-vein case: at least two baskets and two flowers per vein, more if he is not happy.
Intracardiac echo (ICE). Trained in the US with intracardiac ultrasound, he places an ICE catheter from the groin so he can see the catheter seated in the vein before delivering energy — something he says not all operators do.

The speaker’s own sequence, as described in the talk. Other electrophysiologists may use different imaging, catheters and protocols.

The transseptal puncture upgrade

Every left-atrial ablation needs a crossing from the right atrium to the left through the fossa ovalis (he noted everyone has a PFO at birth and in most it seals). Traditionally this uses a long, sharp transseptal needle (71 cm, as captured) through a sheath from the right groin; if the puncture is too anterior or posterior there is a risk of pericardial effusion or worse. RF ablation typically needs two such punctures; cryo and PFA need one.

What excites him most is an atraumatic radiofrequency transseptal wire (product name garbled on ASR): a blunt wire is placed on the septum, a brief burst of RF burns a tiny hole, and the wire forms a soft pigtail that is advanced out to a pulmonary vein, with the sheath following. “Nothing sharp, nothing cutting, nothing stabbing.” Combined with ICE he can see the septum tenting and choose the “Goldilocks” spot. He showed fluoroscopy from recent cases, including a patient with prior CABG and a dual-chamber pacemaker.

Who to refer — and when it is too late

The speaker’s patient-selection rules of thumb, as captured. Individual decisions belong with the treating electrophysiologist.

Does early ablation change the natural history? He acknowledged two schools of thought — does ablation just push the age-related AF curve back ten years, or neutralise it? In his personal experience, some patients ablated 15 years ago as early symptomatic paroxysmal AF still see him every couple of years with no AF. (This is his anecdotal experience, not trial data presented in the talk.)

When ablation is unlikely to work

Continuous AF for more than three years and a left atrium roughly double normal — he quoted a 2D-echo left atrial area of ~20 cm² as normal versus ~40 cm² — means sinus rhythm is unlikely to be maintained. His plan for these patients: rate control and anticoagulation.

Anticoagulation before and after

Before referral: calculate the stroke-risk score (he said CHA₂DS₂-VASc) and, if it is 2 (as best captured), start a DOAC before the patient sees him. Check current Australian guidance — the 2018 NHFA/CSANZ AF guideline uses the sex-neutral CHA₂DS₂-VA score.
After successful ablation: anticoagulation is still mandated by the stroke-risk score “at this point in time”. He mentioned emerging randomised trials and analyses of stopping anticoagulation after successful ablation that may change practice (see the EP Q&A post for the OCEAN discussion).

GP clinic checklist

Symptomatic paroxysmal AF (especially younger, recurrent ED presentations) → refer to EP early; don’t wait for years of drug failure.
Document AF pattern and duration (paroxysmal vs persistent; how long continuous) — it shapes success odds.
Order or forward a transthoracic echo with left atrial size if available; a markedly enlarged atrium with long-standing continuous AF points toward rate control.
Calculate stroke risk and start anticoagulation before referral when indicated.
Counsel patients: PFA is a non-thermal technique with a different complication profile, typically one transseptal crossing, and short energy delivery — but still an invasive procedure with specific risks.
Expect a pre-procedure cardiac CT; post-procedure anticoagulation continues per stroke risk unless the EP advises otherwise.

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