Acute ascending aortic dissection complicating open heart surgery: cerebral perfusion defines the outcome

Incidental Finding of Thoracic Aortic Dissection in a Patient Post-Coronary Artery Bypass Graft Surgery

Thoracic aortic dissection (TAD) is an uncommon but potentially fatal complication of coronary artery bypass graft (CABG). Most patients present to the emergency room with severe chest pain, shortness of breath, or after a syncopal episode. Asymptomatic patients pose a challenge to diagnosis. The authors present a case of an 82-year-old male, who was found to have an incidental finding of a 5-cm ascending aortic aneurysm with an intimal dissection flap four months after CABG. Extensive workup on possible risk factors such as underlying aortic diseases, genetic conditions, and hypertensive crisis proved noncontributory. Aggressive blood pressure control was achieved, and the patient was observed in the intensive care unit before discharge with follow-up. The purpose of this case report is to alert clinicians of TAD after CABG and highlight the importance of developing a protocol for follow-up and monitoring of patients who have undergone CABG, as complications can be asymptomatic. Early and accurate diagnosis of TAD as a complication of CABG is essential to improving survival rates.

Iatrogenic Acute Aortic Dissection in the Era of Minimally Invasive Cardiac Surgery - Experience of a Center and Review of Literature

Introduction

Iatrogenic acute aortic dissection (IAAD) type A is a rare but potentially fatal complication of cardiac surgery.

Methods

The purpose of this article is to review the literature since the first reports of IAAD in 1978, examining its clinical characteristics and describing operative details and surgical outcomes. Moreover, we reviewed the recent literature to identify current trends and risk factors for IAAD in minimally invasive cardiac surgery procedures, often related to femoral artery cannulation for retrograde perfusion.

Results

We found that IAAD ranges from 0.04 to 0.29% of cardiac patients in overall trials and ranged from 0.12 to 0.16% between 1978-1990, before the minimally invasive surgical era. And we concluded that since the first cases to the recent reports, the incidence of IAAD has not significantly changed. As minimally invasive procedures are on the rise, some authors think that the incidence of IAAD could increase in the future; we think that using all the precaution - such a strict monitoring of perfusion pressure throughout the intervention, avoiding extremely high jet pressures using vasodilators, repositioning of arterial cannula, or splitting perfusion in both femoral arteries -, this complication can be extremely reduced. Finally, we describe a very singular case occurring during mitral valve replacement followed by spontaneous dissection of left anterior descending artery one month later.

Conclusion

The present article adds to the literature a more detailed clinical picture of this entity, including patients' characteristics, the mechanism, timing, and localization of the tear, and mortality details.

Angioplasty and stenting for symptomatic stenosis of the left subclavian artery complicated with aortic dissection

BACKGROUND

Aortic dissection is a rare but severe complication of percutaneous transluminal angioplasty and stenting (PTAS) for stenosis of the subclavian artery (SA). This retrospective study was designed to evaluate the risk factors and outcomes of patients with severe stenosis of the SA who underwent PTAS complicated by aortic dissection.

METHODS

Between 1999 and 2018, 169 cases of severe symptomatic stenosis of the SA underwent PTAS at our institute. Of them, six cases complicated by aortic dissection were included in this study. We evaluated the demographic features, technical factors of PTAS, and clinical outcomes in these six patients.

RESULTS

Aortic dissection occurred in 5.3% (6/113) of all left SA stenting cases but in none of the right SA stenting cases. All patients had hypertension and a high severity of SA stenosis (85.0 ± 13.0%, 60%-95%). Five of the six patients received balloon-expandable stents (83.3%). All patients had spontaneous resolution of the aortic dissection with conservative treatment. In a 63.33 ± 33.07 (7-118) month follow-up, five of the six patients (83.3%) had long-term symptom relief and stent patency.

CONCLUSION

Aortic dissection occurred in patients who underwent PTAS for severe stenosis of the left SA, mainly with balloon-expandable stents. We suggest using self-expandable stents and angioplasty with an undersized balloon during PTAS for severe stenosis of the left proximal SA to prevent aortic dissection.

Iatrogenic Aortic Dissection Associated With Cardiac Surgery: A Narrative Review

Iatrogenic aortic dissection (iAD) is a relatively rare but a life-threatening complication associated with cardiac surgery. All members of the team caring for cardiac surgical patients (surgeons, perfusionists, and anesthesiologists) must be familiar with this complication to minimize its incidence and improve outcome. The present narrative review focuses on iAD occurring intraoperatively and during the early postoperative period (within 1 month) of cardiac surgery. The review also addresses iAD that occurs late (beyond 1 month) after cardiac surgery and iAD associated with other procedures. iAD occurs in about 0.06% of cases when the ascending aorta is the site of arterial cannulation, in about 0.6% when the femoral or iliac arteries are used, and in about 0.5% when the axillary or subclavian arteries are used. Mortality is estimated to be 30% but is more than double if not recognized until the postoperative period. Site of origin of dissection is most commonly the arterial inflow cannula (∼33%). Other common sites are the aortic cross-clamp or partial occlusion clamp (∼29%) and the proximal saphenous vein anastomosis site (14%). Sixty percent of cases occur during coronary artery bypass graft (CABG) surgery and 17% during aortic valve surgery with or without CABG. iAD may be somewhat less common in off-pump versus on-pump CABG but is still not very rare. Risk factors, presentation, diagnosis, and management are reviewed in detail as is the key role of the use of echocardiography in the early diagnosis of iAD and for guiding its management.

Iatrogenic acute aortic dissection induced by off-pump coronary artery bypass grifting: A case report and review of the literature

RATIONALE

Iatrogenic acute aortic dissection (IAAD) induced by cardiac surgery is a fatal complication, with 0.04% of therapeutic procedures and worse outcomes than spontaneous aortic dissection.

PATIENTS CONCERNS

A 64-year-old male complaining of intermittent chest tightness for 4 years received an off-pump coronary artery bypass grifting (OPCABG) and IAAD was found during surgery.

DIAGNOSIS

Unstable angina, coronary artery triple vessel lesion, IAAD.

INTERVENTIONS

An ascending aorta replacement surgery was implemented immediately and extracorporeal membrane oxygenation (ECMO) was applied during surgery. The patient suffered from oliguria symptoms and began to receive continuous renal replacement therapy (CRRT) after surgery. What was worse, osteofascial compartment syndrome (OCS) was also confirmed the day after surgery.

OUTCOMES

The CRRT and ECMO were both removed and the condition of the right leg was also stable. But the patient passed away because of uncontrollable sepsis 18 days after the surgery.

LESSONS

OPCABG is clearly the riskiest type of surgery associated with IAADs in cardiac surgical procedures, which should be considered with great concern. Whether ECMO should be used postoperatively in IAAD patients is still a controversial subject, due to some fatal complications linked with it.

Iatrogenic aortic dissection after minimally invasive aortic valve replacement: a case report

BACKGROUND

As minimally invasive cardiac and vascular procedures are on the rise, the incidence of iatrogenic acute aortic dissection (IAAD) will increase. Cardiovascular professionals should be aware about the risk factors, means of prevention and best management options for IAAD in the perioperative setting.

CASE PRESENTATION

We present the successful clinical management of a complicated case of IAAD after minimally invasive aortic valve replacement.

CONCLUSION

High index of suspicion is required for prompt diagnosis of IAAD; collaboration of the whole perioperative team is imperative for management of this catastrophe.

Intraoperative aortic dissection

Intraoperative aortic dissection is a rare but fatal complication of open heart surgery. By recognizing the population at risk and by using a gentle operative technique in such patients, the surgeon can usually avoid iatrogenic injury to the aorta. Intraoperative transesophageal echocardiography and epiaortic scanning are invaluable for prompt diagnosis and determination of the extent of the injury. Prevention lies in the strict control of blood pressure during cannulation/decannulation, construction of proximal anastomosis, or in avoiding manipulation of the aorta in high-risk patients. Immediate repair using interposition graft or Dacron patch graft is warranted to reduce the high mortality associated with this complication.

Retrograde type A aortic dissection after thoracoabdominal aneurysm repair: early diagnosis with intraoperative transesophageal echocardiography

Retrograde type A aortic dissection that arises immediately after open replacement of the thoracoabdominal aorta is a rare and potentially lethal complication that has only been reported twice previously. A 74-year-old man with a history of expanding Crawford type I thoracoabdominal aortic aneurysm presented for open surgical repair. The intraoperative course was unremarkable. However, intraoperative transesophageal echocardiography after the repair revealed type A aortic dissection extending up to the sinotubular junction. Subsequently, emergent aortic arch repair was performed under deep hypothermic circulatory arrest. Early diagnosis with transesophageal echocardiography and optimal cerebral protection were instrumental in the successful outcome of this repair.

Iatrogenic intraoperative type A aortic dissection following cardiac surgery

Background

An increase in the incidence of intraoperative aortic dissection has been reported recently, attributed to the increasingly elderly patient population undergoing cardiac surgery and more off-pump coronary artery bypass. We performed this study to examine current trends, identify risk factors for iatrogenic dissection, and compare iatrogenic intraoperative aortic dissection with spontaneous aortic dissection.

Methods

The 15,144 consecutive patients who underwent cardiac surgery from April 1999 to April 2011 were studied retrospectively on data collected prospectively.

Results

Iatrogenic type A aortic dissection following cardiac surgery was diagnosed intraoperatively in 7 (0.04%) patients. Of the 4784 patients who had off-pump coronary artery bypass, only 2 (0.04%) developed iatrogenic intraoperative aortic dissection. Patients in the iatrogenic aortic dissection group were older by a decade (median age 72 vs. 62 years, p = 0.01). The cannulation site in conventional coronary artery bypass grafting and injury by the side-biting clamp in off-pump coronary artery bypass were the most common causes of dissection. Atheromatous disease was identified at the site of cannulation in 5 (71.4%) of the 7 cases.

Conclusions

Intraoperative aortic dissection remains a rare and unpredictable complication of cardiac surgery, with worse outcomes than spontaneous aortic dissection. Increased age and atheromatous disease at the site of cannulation are significant risk factors for iatrogenic dissection. In this series, off-pump coronary artery bypass did not appear to be a risk factor for iatrogenic aortic dissection.

Case of sudden death from retrograde type A dissection two days after surgery for a type B dissecting aneurysm

A 64-year-old man underwent a descending aortic replacement for a chronic type B dissecting aneurysm with left thoracotomy. The patient was weaned from the mechanical ventilator immediately after surgery without any neurological complications. However, on the second post-operative day, he suddenly suffered from cardiopulmonary arrest when talking with his family. Despite 6 hours of cardiopulmonary resuscitation, the patient died. The postmortem examination revealed a 1000 mL blood volume and huge hematoma in the pericardium owing to a retrograde type A dissection, which descended from an intimal laceration between the common carotid and left subclavian arteries that corresponded with aortic cross clamping. We here report a rare case of iatrogenic retrograde type A dissection caused by surgical clamping on the aortic arch 2 days post-surgery.

Type A Aortic Dissection After Nonaortic Cardiac Surgery

Background—

Cardiac surgery with cardiopulmonary bypass is associated with mechanical manipulation of the ascending aorta that occasionally leads to type A aortic dissection (AAD).

Methods and Results—

One hundred three patients with surgical repair for AAD following nonaortic cardiac surgery were identified. With the use of logistic regression modeling, coronary artery bypass surgery (CABG), either isolated or combined with another procedure in the initial operation, was associated with significantly higher operative mortality in comparison with patients with non-CABG procedures at the time of AAD repair both for all patients (odds ratio, 2.90; 95% confidence interval, 1.09–7.72; P =0.033) and for patients with acute and chronic AAD ≥30 days after the initial operation (odds ratio, 3.62; 95% confidence interval, 1.13–11.54; P =0.03). In patients who developed AAD late after the initial operation, operative mortality was highest in patients without preoperative coronary angiography and appropriate management of their native coronary artery disease and graft disease (odds ratio, 5.36; 95% confidence interval, 1.68–17.0; P =0.002). Nearly all the intimal dissection tears were located at sites of previous surgical trauma. Most of the ascending aortas that had dissected initially had a diameter ≥40 mm with histological evidence of medial degeneration in resected tissue samples.

Conclusions—

In patients who have undergone previous cardiac surgery, preexisting aortic wall pathology contributes to AAD with typical intimal damage at sites of mechanical trauma. The operative mortality was the highest in patients with previous CABG in comparison with patients with non-CABG procedures. Preoperative coronary angiography and operative management of native coronary and graft disease were significantly associated with outcome in patients with previous CABG.

An alternative method for endoaortic clamping in atherosclerotic aorta

To decrease the risk of traumatic injury or dissection of the aorta in patients with diffuse atherosclerotic disease or calcification of the ascending aorta, we have devised a simple method that uses an Embol-X aortic cannula with a Fogarty occlusion catheter.

Eight-year experience of intraoperative aortic dissection

Aortic dissection is a rare but devastating complication of cardiac operations. The purpose of this investigation was to assess the occurrence of aortic dissection during elective cardiac operations and the usefulness of intraoperative transesophageal echocardiography for the diagnosis and management of this complication. Data of consecutive adult patients undergoing elective cardiac surgery with transesophageal echocardiographic monitoring during an 8-year period were studied retrospectively. Aortic dissection was identified in 7 (0.13%) of 5,247 patients, and diagnosed immediately by transesophageal echocardiography in 5 of them; 2 were diagnosed later by transesophageal echocardiography. All aortic dissections were type A and they occurred after completion of the primary procedure. Two patients treated conservatively died within 5 days. Four of the 5 patients who underwent immediate reoperation survived with serious postoperative complications. Transesophageal echocardiography should be carried out when there is a risk of aortic dissection during cardiac operations, especially in the posterior wall of the ascending aorta, to avoid missing the diagnosis and delaying treatment.

Perioperative type I aortic dissection during conventional coronary artery bypass surgery: risk factors and management

OBJECTIVES

Perioperative iatrogenic type I aortic dissection (PIAD) is a rare but potentially fatal complication of conventional coronary artery bypass surgery (CCABG). Prompt recognition and repair of PIAD may significantly improve outcomes.

METHODS

We reviewed the hospital records of patients with PIAD occurring as a complication of CCABG at Siyami Ersek Thoracic and Cardiovascular Surgery Center from January 2001 through June 2007. During this period, 10,130 CCABG were performed and 21 patients (0.20%) with PIAD were identified. We compared variables for these 21 patients with 603 patients without PIAD (control group).

RESULTS

PIAD occurred intraoperatively in 19 patients (90%) and during the early postoperative period (first 6 hours) in 2 patients (10%) who underwent CCABG. Dissections were noticed after removal of the aortic crossclamp in 11 patients, during aortic cannulation in 3 patients, and after removal of the partial-occlusion clamp in 5 patients. Patients with and without PIAD differed significantly in regard to sex (P = .05), history of hypertension (P = .001), and history of severe concomitant peripheral arterial disease (PAD) (P = .001). The diameter of the aorta was significantly wider in patients with PIAD. (3.83 +/- 0.9 vs 2.93 +/- 0.46 cm, P = .019). The occurrence of high cardiopulmonary bypass (CPB) pressure (>==120 mmHg) was significantly higher in the PIAD patients than the non-PIAD patients (28.6% vs 3.3%, P = .0001). Seven PIAD patients (33.3%) died preoperatively and 3 (14.2%) died postoperatively.

CONCLUSION

PIAD is frequently fatal. Risk factors for PIAD during or after CCABG include female sex, history of PAD and hypertension, increased aortic diameter, and high CPB pressure.

Successful Repair of Iatrogenic Acute Aortic Dissection With Cerebral Malperfusion

We describe the successful treatment of a patient with iatrogenic acute aortic dissection including cerebral malperfusion as a complication of coronary artery surgery. After beginning cardiopulmonary bypass, a retrograde ascending aortic dissection associated with cerebral malperfusion was recognized. Systemic circulation was immediately arrested at 31 degrees C. After aortotomy, hypothermic selective antegrade cerebral perfusion was established. Replacement of the ascending aorta with coronary artery bypass grafting was performed without neurologic complications.

Aortic Dissection With Potential Origin From a Mechanical Bypass Anastomosis

Ascending aortic dissection is a known complication of cardiac surgery. Off-pump coronary artery bypass surgery seems to be associated with a higher risk for this event as compared with on-pump bypass surgery. This increased risk may result from aortic side-clamping under pulsatile flow as opposed to continuous flow in conventional bypass surgery. Mechanical devices allowing performance of proximal bypass anastomoses without aortic side-clamping are supposed to reduce the risk for aortic dissection. We report a case in which ascending aortic dissection occurred 8 days after off-pump bypass surgery, most likely arising from a mechanically performed proximal bypass anastomosis.

Differences in Clinical Presentation, Management, and Outcomes of Acute Type A Aortic Dissection in Patients With and Without Previous Cardiac Surgery

BACKGROUND

There are less data on the clinical and diagnostic imaging characteristics, management, and outcomes of patients with previous cardiac surgery (PCS) presenting with acute type A aortic dissection (AAD).

METHODS AND RESULTS

In 617 patients with AAD, we evaluated the differences in the clinical characteristics, management, and in-hospital outcomes of the cohorts with and without PCS. A history of PCS was present in 100 of 617 patients. Patients with PCS were more likely to be males (P=0.02), older (P=0.014), and to have a history of previous aortic dissection (P<0.001) or aneurysms (P<0.001). In contrast, PCS patients were less likely to have presenting chest pain (P<0.001). Cardiac tamponade was less common in PCS patients (P=0.007). Fewer AAD patients with PCS underwent surgical repair (P=0.001). Hospital mortality was not adversely influenced by PCS (odds ratio [OR], 1.46; 95% confidence interval [CI], 0.81 to 2.63), but a trend for increased death was seen in patients with previous aortic valve replacement (AVR) (OR, 2.31; 95% CI, 0.98 to 5.43). Age 70 years or older, previous AVR, shock, and renal failure identified PCS patients at risk for death.

CONCLUSIONS

Our study highlights differences in clinical characteristics, management, and outcomes of AAD patients with PCS. Importantly, PCS, with the exception of previous AVR, does not adversely influence early outcomes of AAD patients, including those undergoing surgical repair. However, because of otherwise dismal outcomes with medical management of AAD, our data indicate that a history of PCS (even that of previous AVR) should not preclude physicians from recommending surgical correction of type A aortic dissection in appropriate patients.

Transesophageal echocardiography-guided closed aortic plication for intraoperative aortic dissection

A 71-year-old female who developed intraoperative aortic dissection after coronary artery bypass grafting underwent a successful closed aortic plication with obliteration of the intimal tear under image guided transesophageal echocardiography.

Successful repair of intraoperative aortic dissection detected by transesophageal echocardiography

Aortic dissection is a rare but devastating complication of cardiac surgery. Early intraoperative diagnosis and management are essential for a favorable outcome. We describe the case of a 69-year-old man with worsening dyspnea who was admitted for mitral valve replacement having previously had a mitral valve repair. Precardiopulmonary bypass transesophageal echocardiography confirmed mitral regurgitation and showed mild atherosclerotic changes in the descending aorta. Following successful replacement of the mitral valve, an attempt to wean from cardiopulmonary bypass failed. This was characterized by acute onset hypovolemia. The transesophageal echocardiography showed the presence of features of acute aortic dissection involving only the descending aorta without identifying the entry point. The tear was successfully repaired by direct suture within the lumen.

Late aortic dissection in a patient with a left ventricular assist device

The limited availability of donor hearts means that an increasing number of transplantation candidates are temporarily or permanently supported by mechanical circulatory assist devices. We report a patient undergoing implantation of a Novacor left ventricular assist device who suffered fatal aortic dissection on postoperative day 11 after satisfactory recovery from multiple organ failure. The dissection of the aorta initially presented as an embolic peripheral ischemia. Early complete echocardiography is thus warranted to rule out dissection.

Acute Dissection of Ascending Aorta after Aortic Valve Replacement

A 57-year-old man who had aortic insufficiency with mild dilatation (36 mm) of the ascending aorta but no evidence of aortic wall degeneration, developed acute dissection of the ascending aorta 6 months after aortic valve replacement. He underwent successful Dacron graft replacement of the ascending aorta.

Increased incidence of acute ascending aortic dissection with off-pump aortocoronary bypass surgery?

BACKGROUND

An apparent increase in the incidence of acute ascending aortic dissection following off-pump coronary artery bypass grafting (OPCAB) led us to assess retrospectively the rate and circumstances of this complication in our institution on a consecutive series of patients undergoing aortocoronary bypass performed with and without extracorporeal circulation (ECC).

METHODS

A retrospective analysis of acute ascending aortic dissections complicating coronary artery bypass grafting surgery in 3,031 patients in our institution since April 1, 1995, was performed using the database of the Montreal Heart Institute.

RESULTS

There was a greater frequency of hypertension in the OPCAB group. Iatrogenic acute aortic dissection occurred in 3 patients among 308 operated on without ECC (0.97%) and 1 patient among 2,723 operated on under ECC (0.04%). This difference was statistically significant (p < 0.00001).

CONCLUSIONS

The risk of aortic dissection may be increased in OPCAB. Careful manipulation of the aorta with a single side-clamping and a control of the arterial pressure should be used to minimize aortic trauma. High-risk patients should undergo CABG without side-clamping of the aorta or CABG with ECC to prevent this redoubtable complication of myocardial revascularization.