PostInfarct Cardiac Free Wall Rupture Detected by Multidetector Computed Tomography
Johann Christopher*
Consultant Cardiologist and Director of Cardiac Imaging, Care Hospitals, Hyderabad, India
*Corresponding author: Dr. Johann Christopher, Consultant Cardiologist and Director of Cardiac Imaging, Care Hospitals, Hyderabad, India. Tel: + 919701445011; Email: johann1403@gmail.com
Received
Date: 29 August,
2017; Accepted Date: 26 September, 2017; Published Date: 05
October, 2017
1. Abstract
48-year-old lady with chest pain is diagnosed to have aninfer posterior MI. 2decho reveals a moderate pericardial effusion post thrombolysis with persistent chest pain. Inview of a possibility of a sealed myocardial rupture she undergoes a coronary CTA to assess the coronary anatomy and to delineate the rupture. The CTA confirms the rupture and delineates the coronary anatomy. Patient undergoes pericardial patch repair with a good result.
2. Keywords:
Multidetector Computed Tomography;
Myocardial Rupture
Introduction
48-years old
lady with history of chest pain of 4 days duration went to nearby hospital,where
she was diagnosed as Infer-Posterior Wall ST elevation Myocardial Infarction
and thrombolysed with streptokinase.
Patient was referred to our hospital in view of moderate pericardial
effusion for further evaluation.
Examination
revealed a pulse rate was 126 beats/min, blood pressure of 100/60 mmHg, her JVP
was elevated. Cardiovascular examinationrevealed normal heart sounds with no
murmur or rub. Respiratory examination revealed few basal crepitations. ECG showed sinus tachycardia,qS in II,III and
aVF with concomitant ST elevation. There were T inversions and ST depression
from V1 to V3.
2D Transthoracic
Echo showed regional wall motion abnormality in basal and mid inferior wall and
inferior septum and basal posterolateral wall, moderate LV dysfunction,preserved
RV function,moderate MR,moderate circumcardiac pericardial effusion. Her blood
analysis was unremarkable.
She was suspected
to have a cardiac rupture and was subjected to a cardiac CT Scan as is the
protocol in our institute where we have diagnosed rupture in ten previous cases
which was proven on surgery.
CT scan with
contrast revealed a sealed myocardial rupture inthe basalposterolateral wallof
left ventricle with a neck of 2mm and an area of 0.8 cm2(Figure 1). CT
coronary angiogram showed total occlusion of a large OM2 branch with grade V
thrombus (Figure 2). Coronary anatomy was
clearly depicted despite her heart rate being above 100 beats per minute which
was corroborated by the coronary angiogram which was done just prior to
subjecting her for surgery.
She
was taken up for emergent surgical repair of cardiac rupture. The pericardial
cavity was filled with 500ml of altered colored blood. There was infarcted and
friable myocardium inposterobasal wall with a rent of 0.5cm near the AV grove. The tear was compatible with the contrast pooling in
the MDCT.The
repair was done with a bovine pericardial patch.
Surgery was
successful with no periprocedural or post-operativecomplications.She was
subsequently weaned off from ventilator support,inotropesand IABP.She made an
uneventful recovery and was discharged in satisfactory condition.
Discussion
Cardiac free wall rupture
after myocardial infarction is one of the life-threatening complications, which
often results in sudden onset of cardiogenic shock caused by cardiac tamponade.
According to the SHOCK Trial Registry, in-hospital mortality rate was 60% [1]. Although the incidence of free wall rupture after
myocardial infarction was 2.7%, the true rate is difficult to assess due to
unconfirmed causes of death, especially pre-hospital death, and diminished
autopsy rates [1]. This complication occurs more
frequently in patients with female gender, advanced age, first-time myocardial
infarction, elevated blood pressure, and transmural infarction [1,2,3]. Ischemic myocardial
rupture after AMI may involve Left Ventricular (LV) and Right Ventricular (RV)
free walls, ventricular septum, and LV papillary muscle, in decreasing order of
frequency. It rarely involves the left or right atrial walls.LAD is the most common site of the culprit artery to
this fatal event, whereas RCA as in the present case is relatively uncommon,
with a reported incidence of 0-23% [1,4].
In
some patients who survive LV free-wall rupture following AMI, the rupture can
be sealed by the epicardium (visceral pericardium) or by a hematoma on the
epicardial surface of the heart. This entity has been referred to as LV
diverticulum (or contained myocardial rupture[5])
and represents a subacute pathologic condition between free rupture into the
pericardial cavity and formation of a pseudoaneurysm.
A
pseudoaneurysm is formed if the area of rupture is contained locally by the
adjacent parietal pericardium and represents the chronic stage of LV free-wall rupture. The
most common etiology of LV pseudoaneurysm was myocardial infarction; inferior
infarcts were approximately twice as common as anterior infarcts[6].
Myocardial free
wall rupture is associated more frequently with thrombolysis especially done
after 6 hours[7].In
the above-mentioned case, delayed thrombolysis was given which could be a
causative factor in Myocardial Free Wall Rupture. As the rupture was contained
by the epicardium, patient did not present with a cardiac tamponade.
In the diagnosis of cardiac rupture, it
is generally difficult to show the defect of the ventricular wall. Pericardial
effusion by CT or echocardiography is only an indirect indicator of an
underlying rupture.In most cases of postinfarct cardiac free wall rupture, the
hemodynamic status is unstable, therefore echocardiography is utilized for
detecting pericardial effusion because of its rapidity and ease. Hence there is
reluctance on the part of the clinician to utilize cardiac CT for the
diagnosis.
MDCT provides valuable information in a patient
suspected of postinfarct cardiac rupture. According to literature research,
there have been few case reports on coincidentally detecting cardiac rupture
after myocardial infarction by means of CT when the scan was undertaken to
detect other pathology like aortic dissection. Redfern and Smart reported a
case of postinfarct cardiac rupture with a tear at the LV apex detected by CT.
They found contrast medium in the pericardial cavity, indicating the spilling
of blood into the pericardial cavity [8]. Naoki Onoda et al. reported a case of cardiac
rupture diagnosed on MDCT with small contrast pooling in the
posterolateral LV wall within a hypoperfused area[9].
This finding is equivalent to free wall rupture within
the infarcted LV wall.
Conclusion
Cardiac CT is a noninvasive, accurate and cost-effective tool for the early diagnosis of cardiac rupture with subsequent appropriate surgical treatment which in turn will improve prognosis in this high-risk subset.
Figure 1:MIP and VRT
Images Depicting the Myocardial Rupture.
Figure 2:MIP Images
Depicting the Coronary Anatomy and the Occluded OM Vessel.
- Slater J, Brown RJ, Antonelli TA, Menon V, Boland J, et al. (2000) Cardiogenic shock due to cardiac free-wall rupture or tamponade after acute myocardial infarction: a report from the SHOCKTrial Registry. J Am Coll Cardiol36:1117-1122.
- Reardon MJ, Carr CL, Diamond A, Letsou GV, Safi HJ, et al. (1997) Ischemic left ventricular free wall rupture:prediction, diagnosis, and treatment. Ann ThoracSurg64: 1509-1513.
- Batts KP, Ackermann DM, Edwards WD (1990). Postinfarction rupture ofthe left ventricular free wall: clinicopathologic correlates in 100consecutive autopsy cases. Hum Pathol 21: 530-535.
- Ishikawa N, Kobayashi A, Ogihara A, Kotaka H,
Shimosato K, et al. (1990) Cardiacfree wall rupture after acute myocardial
infarction. ICU CCU14: 231-237.
- Helmy TA, Nicholson WJ, Lick S, Uretsky BF (2005) Contained myocardial rupture: a variant linking complete and incomplete rupture. Heart 91:e13.
- Frances C, Romero A, GradyD (1998) Left ventricular pseudoaneurysm. J Am CollCardiol 32:557-561.
- Becker RC, Charlesworth A, Wilcox RG, Hampton J, Skene A, et al. (1995) Cardiac Rupture Associated with Thrombolytic Therapy: Impact of Time to Treatment in the Late Assessment of Thrombolytic Efficacy (LATE) Study. JACC 25:1063-1068.
- Redfern A, Smart J (2003) Cardiac rupture. N Engl J Med 348:609.
- Naoki Onoda, Asa Nonami, Toshikazu Yabe, Yoshinori L Doi, Yasufumi Fujita, et al.(2012) Postinfarct cardiac free wall rupture detected by multidetector computed tomography. Journal of Cardiology Cases 5: e147-e149.