Keywords
ischemia/reperfusion - myocardial protection/cardioplegia - surgery - complication
Introduction
Intraoperative myocardial protection with antegrade cardioplegia by selective coronary
cannulation is a widely established and safe technique used in aortic valve surgery.
Injuries to the coronary arteries due to the selective cannulation are a rare but
feared complication.[1]
[2] In this case report, we present an interesting case of diffuse coronary dissection
from the ostium to the periphery of the left coronary system after surgical aortic
valve replacement.
Case Report
A 73-year-old female patient with severe aortic valve stenosis was admitted to an
elective surgical aortic valve replacement with a Society of Thoracic Surgeons score
of 1.62%. Exclusion of a concomitant coronary artery disease was proven by coronary
angiography ([Fig. 1A]). Transthoracic echocardiography revealed a preserved left ventricular ejection
fraction and a thickened bicuspid anatomy of the aortic valve with an opening area
of 0.9 cm2 and maximum and mean pressure gradients of 73 and 44 mmHg, respectively.
Fig. 1 (A) The preoperative angiography of the left coronary artery (LCA), revealing a nondiseased
anatomy. (B–D) The postoperative angiography with dissection of LCA. Dissection begins in the left
main artery with the suspected entry. All marginal branches of the circumflex artery
are affected. Dissection follows the left anterior descending artery until the bifurcation
of the first diagonal branch, continuing in this branch.
After induction of the general anesthesia, a median upper mini-sternotomy was performed
with subsequent initiation of cardiopulmonary bypass. After aortic cross-clamping,
a blood cardioplegia solution was delivered to the aortic root with successful cardiac
arrest. After horizontal aortotomy, antegrade cardioplegia was repeated every 20 minutes
via selective coronary cannulation using coronary perfusion cannulae (SORIN GROUP,
3.0 mm). After aortic valve replacement with a bioprosthesis (Epic™ Supra Valve 23
mm, Abbott Cardiovascular, Plymouth, USA), successful weaning from the cardiopulmonary
bypass was achieved under slight inotropic support without any signs of myocardial
ischemia.
Four hours after surgery, the patient developed hemodynamic deterioration. Electrocardiogram
(ECG) controls showed slight ST-segment elevation in V2–4 with marked elevation of
cardiac biomarkers. Transesophageal echocardiography demonstrated apical and anterior
akinesia that eventually led to urgent coronary angiography. The angiography revealed
a diffuse left coronary artery (LCA) dissection, beginning at the left coronary ostium
spreading to the distal branches ([Fig. 1B], [Videos 1] and [2]). Regarding the left anterior descending (LAD) artery, the dissection continued
into the first diagonal branch, sparing the distal part of the LAD ([Fig. 1B–D]). The RCA was intact. Interventional treatment by stent implantation was discarded
due to the complex character of the dissection challenging identification of a suitable
position in the true lumen. The decision was made to restore myocardial perfusion
by coronary artery bypass grafting to the distal segment of LAD and an obtuse marginal
branch of the circumflex artery.
Video 1 Coronary angiography: Left coronary artery (LCA) in anteroposterior caudal 30 degrees.
Dissection beginning at the left main artery extending to both the LAD and the circumflex
system.
Video 2 Coronary angiography: Left coronary artery in right anterior oblique (RAO) 30 degrees;
caudal 20 degrees. The circumflex system is affected to all marginal branches. Left
anterior descending (LAD) dissection follows the first diagonal branch sparing out
the distal LAD.
Postoperatively, a gradual hemodynamic stability with a rapid decline of cardiac biomarkers
was noted, with subsequent successful termination of inotropic agents. However, after
the antecedent favorable recovery, she suffered from respiratory insufficiency resulting
in reintubation and tracheotomy that were followed by the development of severe pneumonia
and septic shock. Unfortunately, the patient died 61 days after the operation.
Discussion
Coronary artery dissection is a rare but potentially fatal disease ensuing from spontaneous
or iatrogenic origin that is often associated with coronary angioplasty and heavily
affected coronary arteries with an incidence of 0.07 to 0.1%.[1]
[2]
[3]
Our report presents an extensive LCA dissection following a surgical aortic valve
replacement. Iatrogenic coronary intimal laceration following cardiac surgery has
been occasionally reported, though with no described incidence.[3] In this case, selective coronary cannulation was used for cardioplegia perfusion,
which, along with coronary reimplantation and resection of calcic aortic roots, is
a described potential risk factor for coronary dissection.[2]
[4]
The treatment of coronary dissections depends on the resulting cardiac malperfusion
and symptoms. This ranges from a conservative treatment for asymptomatic patients
to a catheter-based intervention or an urgent coronary artery bypass operation.[3] While the previously reported cases experienced catastrophic outcomes with early
death, other recent reports have shown better outcomes that may be associated with
current advances in coronary artery management.[2]
[4] In our patient, an interventional approach was not suitable. Due to the worsening
low cardiac output syndrome, urgent surgical myocardial revascularization was the
only choice remaining. Fortunately, the dissection spared the distal LAD, enabling
revascularization of the anterior wall segment.
The current case corroborates the liberal strategy of early postoperative coronary
angiography if a hemodynamic deterioration, ECG or echocardiographic alteration, or
an obvious increase in cardiac biomarkers occurs. This may help to facilitate early
detection of such an iatrogenic coronary dissection and to enable in-time life-saving
management and thus to minimize the often-fatal subsequent outcome.[4]
