Postoperative Diagnosis:*
1. Type A, Ascending Aortic Dissection
2. Hemiparesis, left
3. Acute respiratory failure
4. Hypertension
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Procedure:
1. Hemi-arch repair of ascending aortic dissection
2. Aortic valve repair with total commissural re-suspension
3. Trans-esophageal echocardiography with visualization and interpretation
4. On-pump cardiopulmonary oxygenator
5. Deep hypothermic circulatory arrest
6. Right femoral artery cut-down
7. Ultrasound guided puncture of the right common femoral artery
Indications:
Ms. woman who presented to the emergency department with stroke-like symptoms. She was intubated upon her arrival. Imaging revealed the presence of a Type A aortic dissection extending from the aortic root distally to abdominal aorta. CT-Head was negative for CVA. Given that her symptoms and presentation were within the window for possible salvage, her family was consented and she was taken to the operating room emergently for the aforementioned procedures.
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Anesthesia:
General
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Wound Classification:
Clean
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Findings:
Pre-bypass TEE: The left ventricle showed concentric hypertrophy and was hyperdynamic. There was no significant mitral regurgitation. The left atrial appendage was well visualized, with no evidence of thrombus. Right ventricular function was normal. There was no tricuspid regurgitation. There was mild aortic insufficiency and no aortic stenosis.
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Post-bypass TEE: On inotropes, showed normal right ventricular function. There was no tricuspid regurgitation. Left ventricular function was hyperdynamic. The left ventricle was adequately de-aired. Aortic insufficiency was unchanged.
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Other intraoperative findings: Acute dissection with a single intimal tear identified along the greater curvature of the ascending aorta. No intimal disruptions visualized in the arch proper.
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Procedure Details:*
The patient had their history and physical updated prior to the procedure. They were then transferred to the operating suite and placed on the operating table where general anesthesia was affected. Monitoring lines and the trans-esophageal echocardiography probe were placed by anesthesia. The patient was then prepped and draped in usual sterile fashion. A surgical timeout was used confirm patient identity as well as the surgery to be performed.
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Next, pre-bypass TEE was performed with findings as described. A a midline sternal incision was made. Dissection was taken down through the soft tissues with elctrocautery. Sternotomy was performed in the standard fashion. The patient was heparinized and ACT was found be therapeutic for cannulation and cardiopulmonary bypass. *Given the patient’s preoperative CTA revealing a possible occlusion of the right common carotid artery at the level of the innominate artery, the decision was made to cannulate the right common femoral artery for cardiopulmonary bypass. Using ultrasound guidance, the right common femoral artery was visualized as patent and accessed using a single anterior wall arterial puncture. A guidewire was inserted and visualized in the true lumen on TEE. Next, using Seldinger’s technique, the artery was serially dilated using the supplied dilators and the femoral cannula inserted. Initially, back bleeding was non-pulsatile and there was concern the cannula had entered the false lumen. At this point, the decision was made to perform a right common femoral artery cutdown. The groin crease was incised with a 10 blade scalpel. With assistance from my assistant, dissection was carried down sharply until the common femoral artery was encountered. The common femoral artery was encircled with vessel loops proximally and distally to the cannula’s entry point. The cannula was removed and arteriotomy identified. The true lumen was identified and a guidewire inserted. The femoral cannula was reinserted, de-aired and attached the cardiopulmonary bypass circuit with pulsatile and adequate line pressure. Central venous cannulation of the heart was then performed and the patient was placed on full cardiopulmonary bypass. A left ventricular vent was placed via the right superior pulmonary vein and the patient was cooled towards 18 degrees centigrade.
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Next, the arch and ascending aorta were dissected free from their surrounding attachments. There was obvious and significant intramural hematoma extending towards the aortic root and into the arch. While cooling, the patient began to fibrillate and the decision was made to cross clamp the aorta and deliver ostial ategrade cardioplegia to achieve full diastolic arrest. A cross clamp was applied and the aorta opened. There was a large tear visualized on the greater curve. The true lumen was entered and coronary ostia identified. Direct ostial cold blood Del Nido cardioplegia was delivered to achieve full diastolic arrest and approximately every 60 minutes while cross-clamped. Cooling continued. Once 18 degrees centigrade had been achieved and we had cooled for 45 minutes, the patient’s head was packed in ice, she was placed in steep Trendelenburg position, exsanguinated and the pump flow turned off.
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Under deep hypothermic circulatory arrest, the ascending aorta was incised and sharply resected circumferentially to the level of the transverse arch. With assistance from the aforementioned assistant, the transverse arch was incised and beveled underneath the origin of the head vessels. There were no additional tears identified at the origin of the arch vessels. A 32mm single side arm gel weave graft was sized and cut to fit the created bevel. A felt sand which was created along the remaining hemi-arch. This was then anastomosed to the beveled graft with running 3-0 Prolene. The arterial return line of the cardiopulmonary bypass circuit was disconnected from the femoral arterial cannula and attached to the side arm of the graft. The graft was de-aired slowly and extracorporeal flow was re-established. A cross clamp was applied to the graft just proximal to the side arm and full flow was resumed. Several repair sutures of 4-0 Prolene were placed along the hemi-arch anastomosis. Hemostasis was verified. The patient was then systemically rewarmed.
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Next, our attention turned to the proximal aorta and aortic root. There were no visible tears identified in the aortic root. The aortic valve was tri-leaflet and somewhat insufficient owing to intimal laxity. All three commissures were re-suspended to coapt height with several pledgeted 4-0 Prolene sutures. Once this was completed, the valve coapted well. A felt sand which was created just above the sino-tubular junction. The proximal gel-weave graft was cut to length and then anastomosed to this point with running 3-0 Prolene suture. A needle vent was placed through the gel-weave graft. The patient was the placed in steep Trendelenburg position and de-airing maneuvers were performed. After adequate de-airing, the needle vent was placed on high suction and the cross-clamp was removed.
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The heart regained rhythm following a single defibrillation. Temporary epicardial pacing wires were placed on the right ventricle and the heart was paced at 80 bpm. Several repair sutures of 4-0 prolene were place in the proximal anastomosis. Hemostasis was verified. The lungs were ventilated. The heart was then weaned from cardiopulmonary bypass without difficulty. Final TEE was performed with findings as described above. Protamine was delivered to reverse the effects of heparin and two rounds of bleeding protocol were ordered. The heart was decannulated. The femoral artery cannula was removed and the artery primarily repaired with interrupted 6-0 Prolene suture. The arterial side arm of the Gel weave graft was divided flush with its base with an endo GIA linear cutting stapler Gold vascular load. Two 32 Fr chest tube were used to drain the mediastinum and single right pleural chest tube was placed.
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Next, the sternum was reapproximated with #7 wires. With assistance from my assistant, the abdominal fascia was reapproximated with 0-looped PDS. The soft tissues were reapproximated with 0 Vicryl. Skin was closed with 4-0 Monocryl in a running subcuticular manner. Dermabond was placed over the wound.
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At this stage, the procedure was discontinued. The patient was transferred to the cardiovascular recovery unit in critical but stable condition.
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Drains:
1 Right pleural chest tubes
2 Mediastinal tubes
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Specimens:
Ascending aorta
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Implants:
32 mm GelWeave single side-arm graft
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Complications:
None
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Estimated Blood Loss:
1000*mL
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Blood Products:
4 units PRBCs
2 units FFP
2 units Cryoprecipitate
1 unit Platelets
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Bypass Times:
CPB: 172 minutes
CCT: 117 minutes
DHCA: 32 minutes