Mohamed Eldeiry, MD, Yihan Lin, MD, MPH, and Muhammad Aftab, MD
University of Colorado, Aurora, CO, USA
This chapter is a revision and update of that included in the previous edition of the TSRA Operative Dictations in
Cardiothoracic Surgery written by Parth Amin, MD, and Joss Fernandez, MD.
Essential Operative Steps
- Invasive arterial pressure monitoring
- Consider spinal drain placement for extensive aortic coverage
- Neuromonitoring
- Percutaneous femoral arterial access for device deployment
- Contralateral percutaneous femoral access for angiogram
- Intravascular ultrasound
- Wire access into true lumen
- True lumen sheath placement
- Confirmation of bilateral through and through true lumen wire access with IVUS (with TEE in thoracic aorta only)
- IVUS evaluation of aortic arch and proximal extent of dissection
- IVUS evaluation of mesenteric and renal arteries
- Angiogram of aortic arch and proximal aorta
- Delivery device for TEVAR graft into true lumen covering the entry tear (with or without left subclavian artery
coverage) - IVUS and angiographic evaluation of proximal aortic repair and perfusion to arch and visceral branch vessels
- Possible extension TEVAR to promote aortic remodeling and perfusion to visceral vessels
Potential Complications and Pitfalls
- Access site complications: It is important to utilize both ultrasound and fluoroscopic guidance to ensure an optimal
femoral cannulation stick. The femoral artery should be entered above the bifurcation (confirmed by ultrasound) and
below the inguinal ligament. Another good marker for the satisfactory stick site is the mid of femoral head which can be
identified fluoroscopically. Always confirm the vascular access needle entry site using ultrasound guidance to ensure that
the femoral cannulation is performed above the bifurcation. This should be balanced with ensuring the access site is not
above the inguinal ligament to prevent a high stick and avoid the retroperitoneal hematoma - Stenting of false lumen: IVUS guidance is key to avoiding this catastrophic complication. It is important to utilize IVUS
upon access to ensure placement of wires and catheters in the true lumen throughout. Endovascular access of upper
extremity vessels may be used to help guide true lumen placement if those vessels are not involved and there is difficulty
accessing from the femoral vessels - Persistent malperfusion of viscera: If despite TEVAR and extension of endovascular aortic repair up to the celiac artery
there is persistent mesenteric or renal malperfusion from dynamic flap or dissection into the branch vessels, there are
several options. Use of a dissection uncovered stent to open the compressed true lumen in the visceral aorta is one option.
Another technique is flap fenestration with or without selective mesenteric branch vessel stenting. As a last resort,
sometimes conversion to open repair to re-establish blood flow to the visceral vessels may be necessary - Lower extremity ischemia: Lower extremity ischemia upon presentation is mostly reversed by timely TEVAR with
coverage of entry tear, opening the collapsed true lumen, and depressurization of the false lumen by re-apposition of
dissection flap. Rarely, persistent unilateral or bilateral lower extremity ischemia – despite endovascular aortic repair –
needs iliac or femoral artery stenting or creation of an extra-anatomical bypass as a last resort. At the conclusion of the
dissection repair, prior to administering protamine for heparin reversal, it is important to check lower extremity pulses
and or doppler signals to ensure that they are unchanged from prior to starting the case – or in the case of lower extremity
malperfusion that flow to the lower extremities has been re-established - Renal failure: This is a dreaded complication of any endovascular procedure due to the nephrotoxic effects of contrast,
and especially if renal malperfusion is found upon presentation. While CO2 injections as a radiopaque agent can be used,
it is often limited by time required between injections to ensure clearance and should be used with caution in patients with
pulmonary hypertension or those suspected of having an arteriovenous malformation or patent foramen ovale - Mesenteric ischemia: Prolonged mesenteric malperfusion can lead to life threatening complications. It is imperative to
obtain revascularization as soon as possible and monitor for ongoing ischemia with serial abdominal examinations,
biochemical markers of end organ ischemia such as lactate, and most importantly keeping a high clinical suspicion to
diagnose it promptly if it occurs. An exploratory laparotomy to assess for visceral ischemia and revascularization might
be necessary in patients with persistent abdominal pain, metabolic acidosis, or lactic acidosis - Lower extremity paralysis: Rarely, spinal cord ischemia from acute type B aortic dissection could present as bilateral
lower extremity paraplegia or paraparesis in settings of well perfused bilateral lower extremities. Sometimes lower
extremity malperfusion from type B aortic dissection could also present as unilateral or bilateral lower extremity
weakness. These conditions could be differentiated by evaluation of lower extremity pulses. Furthermore, immediate or
delayed spinal cord ischemia could occur as a complication of TEVAR
i. There are several adjuncts which could be utilized before or after covered stent development to minimize the risk
of permanent lower extremity paralysis. Preoperative or postoperative lumbar spinal drain placement can be
employed with drainage to a CSF pressure of 8-12mmHg. Intraoperative neurophysiologic monitoring (MEP,
SSEP) could be done for early detection of postoperative spinal cord ischemia, while maintaining the spinal
perfusion pressure (MAP 90-100mmHg) and minimizing blood loss. There are several physiological and
pharmacologic adjuncts including, but not limited to, epidural cooling, intrathecal papaverine, anti-inflammatory
agents (steroids, mannitol), anti-excitotoxic agents (magnesium, naloxone), and barbiturates which can also be
used with data supporting their individual utility in spinal cord protection from ischemia reperfusion - Cerebrovascular accident: This complication could occur from atheroembolic or thromboembolic phenomenon. Wires
and catheters in the arch should be placed after heparinization and after ensuing an ACT >250 seconds. A careful
evaluation of aortic anatomy and arch calcification, particularly around the ostia of arch vessels, is crucial to take
appropriate precautions. Safe wire manipulation technique is also critical for minimizing the risk of embolism or arch
vessel dissection. Wire positioning around arch vessels should be done with caution. Contrast injections above the
diaphragm should be done with extra care to avoid air embolization as well as removal of catheters which can theoretically
lead to suction of air around the catheter. - Retrograde aortic dissection: This is a rare (1-4%) but a potentially life-threatening complication after TEVAR with a
mortality rate of 30-40%. It occurs more frequently after aortic dissection than aneurysm repair. Although it can occur
secondary to wires and catheters manipulation in the aortic arch, other risk factors including fragile proximal aorta (>4
cm ascending aorta diameter), connective tissue disorders, use of stent with proximal struts, presence of angulated (>60°)
“gothic arch”, and >20% oversizing of stent grafts could contribute to this complication. Some centers perform a routine
completion TEE or IVUS to assess the proximal aorta and rule out retrograde aortic dissection at the end of TEVAR to
diagnose this complication. The diagnosis of retrograde aortic dissection warrants an emergency Type A aortic dissection
repair
Template Dictation
Preoperative Diagnosis: Acute Type B (DeBakey III) Dissection with Malperfusion
Postoperative Diagnosis: Same (with appropriate adjustments)
Procedure(s) Performed:
- Ultrasound guided percutaneous access of [right] common femoral artery and catheter placement in the aortic arch for
IVUS and device delivery (or open exposure of [right] common femoral artery) - Ultrasound guided percutaneous access of [left] common femoral artery (or [left] axillary artery) and catheter
placement in the aortic arch for angiogram - IVUS of aortic arch and thoracoabdominal aorta
- Diagnostic angiogram of aortic arch and thoracoabdominal aorta
- TEVAR without (or with) coverage of left subclavian artery using [Stent type, diameter (mm) and length (mm)]
- Extension TEVAR using using [Stent type, diameter (mm) and length (mm)]
- Completion IVUS of aortic arch and thoracoabdominal aorta
- Completion angiogram of aortic arch and thoracoabdominal aorta
- Percutaneous repair of [right] common femoral artery using Proglides x2
- Percutaneous repair of [left] common femoral artery using Proglide x1
- Intraoperative neuromonitoring (SSEP and MEP) – optional
- Intraoperative TEE – optional
Attending Surgeon: [BLANK]
Secondary Surgeon: [BLANK]
Assistants: [BLANK]
Anesthesia: [BLANK]
Contrast: [mL, type of contrast]
Indication(s) for Procedure: This is a [AGE / SEX] patient who presented with acute onset chest and back pain and was
diagnosed with an acute type B aortic dissection. The patient developed progressively worsening symptoms of (lower extremity
weakness, pain in both or one leg/abdominal pain/flank pain). Their CT scan demonstrated an acute type B aortic dissection
with an entry tear distal to the left subclavian artery. There was a severely compressed true lumen distal to the large entry tear
and a significantly large false lumen leading to distal arterial malperfusion to the [kidneys, intestine, and/or lower extremities].
Given the complicated type B dissection, we discussed various treatment options as well as the benefits and risks of proposed
TEVAR. I explained to the patient that with acute type B aortic dissection with malperfusion, urgent intervention is indicated.
The goals of TEVAR are to address the life-threatening malperfusion and to cover the entry tear leading to decompression of
the false lumen, repressurization of the true lumen, and return of perfusion to the visceral vessels. Discussion was also carried
out with the patient on other treatment options including open and endovascular fenestration, in addition to TEVAR, and
possible bypass. The risks of surgery include, but are not limited to, infection, access site complications needing open repair
of femoral/iliac vessels, bilateral lower extremity early or delayed paraplegia or paraparesis needing further procedures and
possible lifelong extremity weakness, stroke, retrograde aortic dissection requiring open surgical possible arch repair, renal
failure requiring dialysis, inability to restore flow requiring open surgical repair or bypass to address the malperfusion, endoleak
needing further procedures, possible coverage of left subclavian artery requiring left arm revascularization, blood or blood product transfusion, and moderate risk of death. The patient asked numerous insightful questions which were answered to their satisfaction. An informed consent was obtained. Description of the Procedure: After patient identification, surgical site confirmation, and informed consent, the patient was brought to the hybrid operating room, and positioned on the operating table in a supine position. A left radial arterial line and large bore venous access sites were placed. [Optional – A lumbar drain was placed pre-operatively by the interventional team and ensured to be patent and draining at 10 mm Hg. Neuromonitoring probes were placed for analysis of motor and somatosensory evoked potentials]. The patient’s right arm, chest, abdomen and groins were then prepped and draped in a sterile fashion. The preoperative CT scan revealed that the [RIGHT/LEFT] femoral artery was perfused by the true lumen. Ultrasound guided percutaneous [right] common femoral arterial access was obtained with modified Seldinger technique using a micropuncture system. Angiogram confirmed the optimal puncture site in the common femoral artery. The access was upsized to a 5Fr sheath. Two Proglides were then deployed at 10’o clock and 2’o clock positions for preclosure and a 9Fr sheath was placed. The sutures were secured and separated from the operating field for later use. Contralateral common femoral artery access was obtained in a similar fashion using micropuncture needle and wire. This access was upsized to a 5Fr sheath for catheter placement in the aortic arch and descending thoracic aorta for angiogram. [If cut down was performed]: A [right] femoral cut down was performed using a transverse incision 1cm below the inguinal ligament. The femoral artery was circumferentially dissected and controlled. Systemic heparin was then administered. A micropuncture system was used for femoral access and exchanged for a 9Fr sheath. Contralateral percutaneous femoral access was then obtained with a micropuncture system. [If femoral access vessels are too small for delivery device]: A transverse incision was made in between the anterior superior iliac spine and the umbilicus. The anterior fascia was incised, the muscle split, and the retroperitoneal plane entered. The iliac bifurcation was identified, circumferentially dissected, and controlled. After adequate heparinization, the iliac artery was clamped, an arteriotomy made, and a standard 6-0 prolene running anastomosis was performed to a 10mm Dacron graft in endto-side fashion. Systemic heparin (150 u/kg) was then administered to achieve a goal ACT >250 seconds. After ensuring an adequate ACT, a 0.035inch glide wire and KUMPE (KMP) or glide catheter taken to the aortic arch from the [right] common femoral approach. [Optional: TTE was used to confirm the presence of glide wire in the true lumen of the thoracic aorta]. The glide wire was then advanced to the arch of the aorta under fluoroscopic guidance. IVUS was then used to confirm location of the wire with through and through presence of wire access in the true lumen. The entire aorta was systematically evaluated starting from the ascending aorta into the aortic arch and the entry tear of dissection was identified distal to the left subclavian artery. Extension of dissection into the arch branch vessels was evaluated and none was found. Both proximal and distal landing zones were evaluated. Visceral vessels were further investigated for their origin from true and false lumen and for any dynamic compression. The left renal vein was used as a landmark to identify the celiac artery, the superior mesenteric artery, and the renal arteries. The following vessels were fed by the true lumen [mesenteric, renal, lower extremity]. Malperfusion to the [mesenteric, renal, lower extremity] vessels were noted on IVUS. Pressure measurements were also taken in the true lumen using a standard 5Fr catheter. IVUS pullback was performed, and images captured. Both the proximal and distal landing zones were measured using IVUS and these findings were correlated with CTA measurements and the device was selected with <10% oversizing. Similarly, from the [left] common femoral artery a glide wire and KMP catheter were advanced under fluoroscopy and the wire was positioned in the aortic root, just above the aortic valve. Again, wire access was ensured to be in the true lumen by an already placed IVUS catheter from the [right] common femoral artery. [Alternatively, [left] 5Fr access can be upsized to 9Fr sheath after placing a proglide at the 12 o’clock position and IVUS can be performed from the left common femoral artery as well to ensure the wire access in the true lumen throughout]. [If difficulty in accessing true lumen]: Right brachial access was performed using a micropuncture system and exchange performed to a 5Fr sheath. A 300cm angled 0.035inch Glidewire was advanced from the right arm into the aortic arch. A snare was then brought from the femoral approach and used to bring the right arm wire to the [RIGHT/LEFT] femoral artery. IVUS was then used to confirm the wire location in the true lumen. Bare metal stents in the infrarenal aorta and iliofemoral arteries may be required to expand the true lumen and alleviate the malperfusion syndrome. Based on IVUS localization, the intimal defects or fenestrations were marked. The proximal and distal landing zones were then marked at minimum 2cm proximally and distally. After the access wire was exchanged for a stiffer wire, the delivery device was taken to the descending thoracic aorta. Next, preoperative arch angiogram was performed, and origin of arch branch vessels was identified and marked from proximal stent graft deployment. The systolic blood pressure was brought down to 100-110mmHg and mean to 60mmHg. After a breath hold, the thoracic stent graft was deployed. The pigtail catheter was taken to the aortic arch and then another angiogram was taken. The graft was confirmed to be in the appropriate position. Significant reduction in perfusion of the false lumen was noted. Additional angiographic views of the mesenteric, renal, and iliac vessels were undertaken. Contrast was noted to fill in an antegrade fashion, with no delay, in all the vessels noted. [If individual branch vessel malperfusion is still present]: Wire access was then obtained into the [mesenteric, renal] artery with malperfusion. A Glidecath system was then used to access the orifice of the vessel. Once in the vessel, the system was exchanged to a 0.014inch wire platform. An angiogram was performed, and sizing determined. A balloon expandable stent was then deployed from the true lumen into the branch vessel. Repeat angiogram showed perfusion of the stented artery. [If the true lumen of the visceral aorta is still compressed compromising multiple branch vessels]: Endovascular fenestration was performed. IVUS is introduced into the [right] femoral access where the wire has been confirmed to be in the true lumen.
After a wire was placed across a more proximal fenestration, a snare was brought to capture the wire from below. The snared
wire was then pulled down, causing a tear in the intimal flap. Once the fenestration was created, IVUS was repeated to confirm
fenestration and branch vessel patency.
The catheters were removed over an Amplatz wire and the Proglide devices were deployed simultaneously with adequate
hemostasis over the wire. The wire was then removed, and the sutures were pushed down further onto the vessels and locked.
Pressure was held until protamine was administered ensuring adequate pulse/doppler signals and left on for 15 minutes until
adequate hemostasis was achieved.
The wires and catheters were removed. The arterial exposure was closed with a running 5-0 prolene suture. The wound was
then closed in multiple layers. The distal pulses were evaluated and were [PALPABLE/AUDIBLE ON DOPPLER]. The
patient was taken to ICU in stable condition, having tolerated the procedure well.
Dr. [BLANK] was present and scrubbed for [BLANK] elements of the procedure.
Multiple Choice Question(s)
While placing the proximal stent in the descending aorta, the left subclavian artery is covered inadvertently, what is your course
of action?
A. Perform thoracoabdominal repair and remove stent
B. Check pulse ox and arterial waveform in the left arm
C. Perform emergent carotid-subclavian transposition
D. Perform emergent carotid-subclavian bypass
Answer B.
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