Lorenzo A. Menicanti, MD
IRCCS Policlinico San Donato Hospital, Milan, Italy
Editorial commentary on an article entitled: An historical appraisal of
the techniques of left ventricular volume reduction in ischemic
cardiomyopathy: who did what?
No conflict of interest exists
Funding statement: none
Total words: 1198
Address for Correspondence:
Lorenzo A. Menicanti, MD
IRCCS Policlinico San Donato
Head of Cardiac Surgery Department
Scientific Director
Via Morandi 30 - 20097 San Donato Milanese
Milan, Italy
Email: lorenzo.menicanti@grupposandonato.it
Phone + 39 52774514 - 4521
Fax + 39 52774327
The surgical treatment of left ventricle aneurysm is a well-established
procedure and the guidelines of the treatment of coronary artery disease
consider the procedure with an evidence IIA 1.
The story of this procedure started long time ago when Beck2 in 1944
reduced the volume of a left ventricle aneurysm with a fascia lata
patch, secured to the pericardium; the patch is plicate in length
bringing near the borders of the pericardium, in this way the dilatation
of the left ventricle stuck to the pericardium is reduced.
Calafiore and coworkers3, in this issue of Journal of Cardiac Surgery,
describe the evolution of treatment from Beck’s first attempt to more
recent techniques, using Extracorporeal Circulation and Cardioplegic
arrest, non-available at Beck’s time.
Calafiore describes in a complete and elegant way the different
techniques performed to achieve the same result: rebuild a left
ventricle cavity with dimension and shape as more physiological as
possible. All major contributions are described.
Correctly, there is no mention of Batista 4 procedure; this procedure
was proposed for patients with very large left ventricle and increased
wall thickness determined mainly by Chagas disease. In this pathological
situation, the outcomes were positive; in opposite when ischemic patient
were treated with this technique, the results were poor. This could have
been expected: the Batista procedure resects a portion of lateral wall.
When a dilatation of left ventricle, after AM,I is present , in majority
of cases, is due to an occlusion of left anterior descending coronary.
The anteroseptal portion of the left ventricle is scarred and the
lateral wall is one of the functioning parts of left ventricle. If a
portion is resected, the volume is reduced but it can harm the
contractile function of lateral wall.
After an Acute Myocardial Infarction, involving the LAD territory, it is
possible that the scar tissue increases in extension, producing a
classical left ventricle aneurism with a well-defined neck and a
transitional zone between the scar and normal contractile myocardium
with normal wall thickness.
However, when the scar extension involves a larger area in the
antero-septal-apical region, the classical phenotype of left ventricle
aneurism with a well-defined neck dividing the contractile basal portion
from the akinetic or diskinetic anteroseptal apical region, is not
present anymore. This anatomical presentation cannot be described as
Left Ventricle Aneurysm but rather as an Ischemic post-AMI
Cardiomyopathy5. The pathology is of course the same but the effects on
the function and shape of ventricle are more complex and detrimental.
Nowadays this clinical presentation is more frequent because of the wide
use of primary PCI, aggressive medical therapy and PCI performed very
frequently in follow-up period of these patients.
All these treatments reduce the mortality of AMI, but increase the
number of patients with an enlarged left ventricle and heart failure.
In case of a primitive cardiomyopathy, the thickness and the
contractility of left ventricle wall is reduced in all segment in a
homogenous way, differently from a Left Ventricle Aneurysm or dilated
ischemic post AMI cardiomyopathy, where, segments have different
thickness and function: reduced in scarred zone and near normal in
remote zone. The success of the left ventricle reconstruction procedure
depends on the extension and function of the myocardium far from the
infarcted area6.
In these pathophysiological conditions, the wall stress induced by the
increased cavity volume, increases oxygen consumption and decreases the
contractile reserve mainly in normal functioning part of the ventricle.
Consequently, the reduction of left ventricle volume leads to a
reduction of wall stress, decreasing oxygen demand and increasing
contractile reserve. The reduction of heart failure markers after
Surgical Ventricular Restoration is the demonstration of this positive
effect7.
The shape of the ventricle is important: an ellipsoid shaped ventricle
has a better mechanical resynchronization and avoiding sphericalizazion
improves the function of mitral valve and decreases the risk of
diastolic disfunction.
Surgical Ventricular Restoration or Reconstruction before being a
surgical technique is a clear Concept. The Surgical Procedure to be
effective has to achieve:
a) Effective Left Ventricle Volume Reduction (less than 60 ml / m2 ESVI)
b) Sphericity Index in normal range avoiding value below 0.6
c) Complete coronary revascularization
All surgical techniques achieving these targets are good treatments
regardless the authors and modifications.
The main differences between techniques consist in using a sizer to
define precisely the target volume and the use of a prosthetic patch to
rebuild the left ventricle cavity.
The baseline characteristics of ventricle can determine the final shape
and volume.
There are some situations very favorable; in which the base of
dilatation is small and the longitudinal diameter is preserved. Closing
the base in every way, (purse string, small patch, linear closure)
comfortable for the surgeon brings a good result but unfortunately
similar situation is very rare.
Conversely, let assume to have a big ventricle with a large base
parallel to the plane of mitral valve with reduction of basal to apex
diameter, in this situation not all techniques can achieve the same
result, with the possibility to determine a sphericalizazion with an
incorrect control of the volume.
When an occlusion of the LDA produces a severe dilatation of
antero-septal portion of the left ventricle, the dilatation can involve
not only the apex of ventricle but also, extending around the apex, the
inferior wall. In this situation, the transitional zone is almost at the
base of papillary muscles.
Calafiore describes very similar situation in fig. 4 and 6 of his paper.
In Fig. 4 the inferior dilatation is unchanged, in Fig. 6 it is evident
the important reduction of longitudinal diameter of the left ventricle.
A sizer, chosen according to Body Surface Area of patients, inserted in
the cavity of left ventricle gives to surgeon two information: the
position of the new apex, keeping in the normal range the longitudinal
diameter and the target volume8.
Scar tissue is often present between the transitional zone very near to
the base of papillary mussels, and the position of the new apex pointed
by the sizer. A plication of the scarred wall can be performed starting
from the base of the papillary and reaching the apex of sizer. In the
way the inferior dilatation is obliterated, this plication with a very
short suture, less than two centimeters, allows to respect the
longitudinal diameter of left ventricle, avoiding sphericalizazion.
The sizer indicate also the target volume; the cavity can be closed with
a linear suture over the sizer bringing the anterior wall against the
septum, and excluding from the cavity the scar tissue of the septum in
the same way described in Fig. 3 in Calafiore paper.
After an AMI, Surgical Ventricular Reconstruction is a very powerful
tool in the hands of surgeons for restoring a ventricle with volume and
shape very close to normal. The exclusion of scar tissue from the left
cavity reduces left ventricle volume, reaching the target of 60 ml/m2
ESVI. The use of sizer allows a better reconstruction, pointing out the
correct position of the new apex. The result will be a ventricle of
targeted volume and physiological ellipsoidal shape. All types of
phenotypes dilatation can be approached avoiding the use of a patch to
get a shape with a sphericity index near to normal.
References
- Neumann FJ, Sousa-Uva M, Ahlssom A, et al; 2018 ESC/EACTS Guidelines
on myocardial revascularization: The Task Force on Myocardial
Revascularization of the European Society of Cardiology (ESC) and the
European Association for Cardio-Thoracic Surgery (EACTS) Developed
with the special contribution of the European Association of
Percutaneous Cardiovascular Interventions (EAPCI). Eur Heart J. 2018;
00:1-96
- Beck CS. Operation for Aneurysm of the Heart. Ann Surg 1944;
120:34-40.
- Calafiore AM, Totaro A, Prapas S, et al. An historical appraisal of
the techniques of left ventricular volume reduction in ischemic
cardiomyopathy: who did what? Journal of Cardiac Surgery 2021(in
press)
- Batista RJ, Verde J, Neri P, et al. Partial left ventriculectomy to
treat end-stage heart disease. Ann Thorac Surg 1997; 64: 634-38.
- Menicanti L, Castelvecchio S, Left ventricular reconstruction. In
Mastery of Cardiothoracic Surgery, by Larry Kaiser, Irving Kron, and
Thomas Spray – Third edition 2014; 54: 519-31.
- Castelvecchio S, Careri G, Ambrogi F, et al. Myocardial scar location
as detected by cardiac magnetic resonance is associated with the
outcome in heart failure patients undergoing surgical ventricular
reconstruction. Eur J Cardiothorac Surg. 2018; 53:143-49.
- Castelvecchio S, Baryshnikova E, Pina IL, et al. Longitudinal profile
of NT-proBNP levels in ischemic heart failure patients undergoing
surgical ventricular reconstruction: The Biomarker Plus study. Int J
Cardiol. 2018; 260: 24-30.
- Castelvecchio S, Pappalardo OA, Menicanti L, Myocardial reconstruction
in ischaemic cardiomyopathy, Eur J Cardio-Thoracic Surg. 55 (2019)
i49-i56.