1. Complete electrophysiologic study with induction.
2. Placement of left femoral arterial sheath for pressure monitoring.
3. Intracardiac echocardiography.
4. Aborted ablation of left ventricular tachycardia.
INDICATIONS: The patient is a 63-year-old gentleman with a history of
atherosclerotic heart disease. Previous inferolateral myocardial
infarction. Known total occlusion of the right coronary artery.
Nonobstructive disease involving left anterior descending coronary artery,
circumflex coronary artery, and ramus intermedius based on cardiac
catheterization approximately 2 years ago. History of ventricular
tachycardia. Existing dual-chamber ICD (St. Jude). Recurrent symptomatic
ventricular tachycardia. Ventricular tachycardia characterized as left
axis, right bundle branch block morphology consistent with left ventricular
origin. Resulted in multiple ICD discharges. Recent PET scan positive for
old infarction. Negative for ischemia. Left ventricular ejection fraction
0.40-0.45. Planned electrophysiologic testing to determine number of
inducible ventricular tachycardias with an eye towards VT ablation (left
ventricular ablation).
PROCEDURE DESCRIPTION: After informed consent was obtained, the patient
was transported to the cardiac electrophysiology laboratory in the
postabsorptive, nonsedated state. He was placed on the table in the supine
position. The right and left groins were prepped and draped in the usual
fashion. Local anesthesia of both groins was attained using 1% lidocaine.
The left femoral artery was percutaneously punctured with an 18-gauge
thin-wall needle, and a 5.5 French arterial sheath positioned in the
artery. Left femoral arterial pressure was monitored throughout the case.
The left femoral vein was percutaneously punctured with an 18-gauge
thin-wall needle, and an 11 French venous sheath positioned in the vein. A
10 French intracardiac echo probe was advanced through the 11 French venous
sheath, and positioned in the right atrium. Intracardiac echocardiography
was performed. The intracardiac echocardiogram revealed a small
pericardial effusion that was primarily posterior. Additionally, there was
evidence of the extensive infarction involving the inferior and part of the
inferolateral wall of the left ventricle with a transition zone from
infarcted tissue to healthy tissue in the region of the inferoapical and
inferoseptal left ventricle.
Left ventricular ejection fraction is felt to be 0.35-.40 based on
intracardiac echocardiography. The right femoral vein was percutaneously
punctured on 3 separate occasions, and 6.5 French and 6 French venous
sheath positioned in the vein. Three 6 French quadripolar electrode
catheters advanced through the venous sheath under fluoroscopic guidance,
and positioned in the high right atrium, His bundle region, and right
ventricular apex. Complete electrophysiologic testing was performed.
Basic conduction intervals were recorded. Baseline EKG was recorded. Sinus
node recovery times were not performed. Incremental atrial pacing was
performed from the high right atrium until antegrade block occurred.
Incremental ventricular pacing was performed from the right ventricular
apex until retrograde block occurred. Antegrade refractory periods
performed from the high right atrium at drive cycle length of 600 msec.
Retrograde refractory period was performed from the right ventricular apex
at a drive cycle length of 600, 500, and 400 msec.
Double ventricular extrastimuli were introduced at the same drive cycle
lengths. The patient had reproducible inducible monomorphic sustained
ventricular tachycardia 2 morphologies. This was inducible at all 3 drive
cycle lengths using single and double ventricular extrastimuli. The
slowest ventricular tachycardia was the previously documented clinical
ventricular tachycardia. This was a left axis, right bundle branch block
morphology with a cycle length of 412 msec. The second morphology was
faster and had a northwest axis right bundle branch block cycle length of
322 msec. Both tachycardias were easily reproducible inducible and were
noted to be sustained. Both were terminated with ventricular burst pacing.
It was elected to proceed with left ventricular VT ablation. It was
elected to proceed with a retrograde approach. The aortic valve had been
previously noted by transthoracic echocardiography, and was noted by
intracardiac echocardiography to not be sclerosed or calcified and not
stenotic. The right femoral artery was percutaneously punctured with an
18-gauge thin-wall needle, and an 8 French sheath was positioned in the
artery.
An 8 French Biosense Webster SF ThermoCool ablation catheter was advanced
into the 8 French sheath out into the femoral artery. As the catheter was
being advanced up through the right iliac, it became clear that the iliac
was fairly heavily calcified, and was at risk for dissection of a plaque.
Therefore, the catheter was withdrawn. An 8 or 9 French 60 or 90-cm sheath
was requested. However, neither of these were available. A 9 French,
30-cm sheath was available. The standard 9 French sheath was exchanged out
for the 30-cm sheath. This sheath ended at the origin of the right common
iliac artery.
The ablation catheter was advanced through the sheath into the distal
aorta. The aorta was fairly heavily calcified and somewhat tortuous. The
ablation catheter was advanced into the descending aorta, and navigated
into what appeared to be the true lumen. The catheter was advanced up into
the thorax without any difficulty. However, in the descending thoracic
aorta obstruction was reached. The catheter was withdrawn. A 0.035
J-tipped guidewire was advanced through the sheath into the aorta. This
followed the same path as the ablation catheter. Again, it reached a
terminal point in the descending thoracic aorta distal to the takeoff of
the left subclavian artery.
A 6 French JR-4 coronary catheter was advanced over the guidewire. Gentle
hand injection was performed revealing that the guidewire catheter were in
a false lumen. Obviously, the ablation catheter resulted in a retrograde
aortic dissection extending from the abdominal aorta into the thoracic
aorta. The coronary catheter was withdrawn. Utilizing the coronary
catheter and the guidewire, the true lumen of the aorta was found. The
guidewire was advanced through the true lumen of the aorta into the
ascending aorta across the aortic valve into the left ventricle. The JR-4
guide catheter was advanced over the guidewire, and positioned in the
aortic arch.
Aortic arch angiography was performed. This did not reveal an antegrade
rent/tear in the thoracic aorta. The catheter was withdrawn into the
descending thoracic aorta. Hand injection aortography was repeated. Again,
no antegrade entry into the aortic dissection/false lumen was noted. The
entire catheter was withdrawn. At this point, it was felt best to abort any
attempt at ablation of the left ventricular tachycardias.
Heparin was discontinued and reversed with protamine. All sheaths were
withdrawn. Firm pressure was applied to both groins for 20 minutes. After
hemostasis was attained, distal pulses were noted to be baseline. A
nonpressure dressing was applied to both groins. The patient was
subsequently transported to his room in stable condition.
MEDICATIONS ADMINISTERED: Lidocaine 1% local anesthetic. Heparin 14,000
units IV. Heparin drip up to 1100 units per IV. Versed 6 mg IV. Fentanyl
125 mcg IV. Nasal oxygen at 3 liters per minute.
FLUOROSCOPY TIME: Less than 10 minutes.
CONTRAST: Visipaque 60 mL total.
ESTIMATED BLOOD LOSS: None.
COMPLICATIONS: Retrograde dissection of the abdominal aorta extending into
the thoracic aorta secondary to advancement of the ablation catheter
through the aorta. No evidence of an antegrade connection to the false
lumen based on aortic arch and descending thoracic aortography.
EQUIPMENT MALFUNCTION: None.
TECHNICAL DIFFICULTIES: As noted above, difficulty occurred with passage
of the ablation catheter retrograde through the aorta. A 60, 70, or 90-cm 8
or 9 French sheath was requested. However, no sheath was available for
use.
RESULTS:
I. Basic Conduction Intervals:
Initial: Sinus cycle length 110 msec. PR interval 186 msec. QRS duration
176 msec. QT interval 478 msec. PA interval 50 msec. A-H interval 92
mesc. H-V interval 52 msec.
Baseline EKG revealed sinus rhythm, normal axis, right bundle branch block,
old inferior wall myocardial infarction.
Conclusion: Cycle length 1052 msec. PR interval 178 msec. QRS duration
168 msec. QT interval 420 msec. PA interval 32 msec. A-H interval 9 msec.
H-V interval 56 msec.
Concluding EKG: Normal sinus rhythm, normal axis, right bundle branch
block, old inferior wall myocardial infarction.
II. Functional Properties:
A. Sinus Node - Sinus node function noted tested.
B. AV node: AV node conduction appears to be normal.
1. Resting A-H interval 92 msec.
2. Maximum 1:1 AV node conduction atrial pacing 540 msec.
4. AV node block cycle length (Wenckebach) 530 msec.
5. No dual AV node pathways noted.
6. No dual AV node pathway is noted.
7. Antegrade refractory period is AV node: Normal.
Pacing HRA Cycle Length (msec) Effective Refractory Period (msec)
600 380
6. There was no retrograde conduction. There was no VA conduction.
C. Atrial refractory periods: Not performed.
D. Retrograde refractory periods: Normal.
Pacing RVA Cycle Length (msec) Effective Refractory Period
(msec)
600 260
500 260
400 250
III. Arrhythmias induced.
A. There was no evidence of an atrioventricular accessory pathway. No
pathway was observed during sinus rhythm, incremental atrial pacing, or
retrograde refractory period determination. There was no retrograde
conduction. There was no VA conduction.
B. Supraventricular arrhythmias: None induced.
C. Ventricular arrhythmias: There was reproducible inducible monomorphic
nonsustained and sustained ventricular tachycardia from the right
ventricular apex using 1 and 2 ventricular extrastimuli at drive cycle
lengths of 600, 500, and 400 msec. The reproducible inducible monomorphic
sustained ventricular tachycardiac at 2 morphologies. One morphology was
identical to the patient's clinical morphology, and was characterized as a
left axis, right bundle branch block morphology, cycle length 412 msec.
The second morphology was characterized as a northwest axis, right bundle
branch block morphology cycle length 322 msec. Both morphologies of
sustained ventricular tachycardiac were terminated with ventricular burst
pacing.
As noted above, ablation of the 2 morphologies of left ventricular
tachycardia was aborted secondary to the complication of retrograde aortic
dissection of the abdominal aorta extending into the thoracic aorta that
occurred during advancement of the ablation catheter retrograde through the
abdominal aorta. The aorta was noted to be tortuous and significantly
atherosclerotic with obvious calcium.
RECOMMENDATIONS:
1. The patient's ICD was reprogrammed as desired and as had been noted at
the time of presentation. During the case, the therapies obviously were
turned off, and the device had been reprogrammed to the VVI mode at 40
pulses per minute.
2. Continue current medical therapy.
3. The patient will be monitored for an extended period of time in our
cardiac observation unit. If he develops any abdominal pain or back
pain, CT angiography will be performed.
4. The patient will ultimately require readmission and second attempt at
ablation of the 2 morphologies of ventricular tachycardia that have been
recurrent, resulting in ICD discharges. There are left ventricular
tachycardias. The case will be approached from a transseptal approach
utilizing a Mullins sheath with ablation catheter being advanced through the
Mullins across the mitral valve for left ventricular ablation.
However, the retrograde approach must be utilized in backup fashion
should the ablation not be accomplished with the transseptal approach.
Therefore, a 90-cm 9 French sheath will be needed. The sheath will be
needed for passage of the catheter through the aorta in a retrograde
fashion. This procedure will be performed in 4-6 weeks after the
current retrograde aortic dissection has healed.
aborted ep ablation
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