Nigerian Journal of Cardiology

ORIGINAL ARTICLE
Year
: 2014  |  Volume : 11  |  Issue : 2  |  Page : 124--126

Short-term outcome of cardiac resynchronization carried out at the Madras Medical Mission, India


Kelechukwu Uwanuruochi1, Anita Ganasekar2, Benjamin Solomon3, Ravi Kumar Murugesan3, Jaishankar Krishnamoorthy4, Ulhas M Pandurangi4,  
1 Department of Medicine, Federal Medical Centre, Umuahia, Nigeria; Department of Cardiac Electrophysiology, Institute of Cardio-Vascular Diseases, Madras Medical Mission, Chennai, Tamil Nadu, India
2 Department of Cardiac Electrophysiology, Institute of Cardio-Vascular Diseases, Madras Medical Mission, Chennai, Tamil Nadu, India
3 Cardiac Catheterization Laboratory, Institute of Cardio-Vascular Diseases, Madras Medical Mission, Chennai, Tamil Nadu, India
4 Department of Cardiology, Institute of Cardio-Vascular Diseases, Madras Medical Mission, Chennai, Tamil Nadu, India

Correspondence Address:
Kelechukwu Uwanuruochi
Department of Medicine, Federal Medical Centre, Umuahia, PMB 7001, Nigeria

Abstract

Background: Cardiac resynchronization therapy (CRT) is a relatively new therapy for patients with symptomatic heart failure resulting from systolic dysfunction. The procedure is carried out regularly in the Cardiac Catheterization laboratory of Madras Medical Mission, India. Objective: We sought to determine the benefit of cardiac resynchronization therapy in patients followed up at the centre. Methods: We retrospectively studied cases of cardiac resynchronization therapy carried out at the Madras Medical Mission over the past five years with respect to clinical as well as echocardiographic changes from the time of implantation to follow-up. Results: After a mean interval of 11.32 ± 9.25 months the improvements were observed as follows: Mean heart rate 77.94 ± 16.58/min to 69.13 ± 8.37/min (P = 0.066), mean systolic blood pressure 121.13 ± 16.33 mmHg to 131.73 ± 16.85 mmHg (P = 0.022), mean NYHA class, 3.27 ± 0.57 to 1.69 ± 0.67 (P = 0.000), QRS duration 169.39 ± 0.17 ms to 125.40 ± 24.40 ms (P = 0.000), mean ejection fraction 27.56 ± 5.47 to 38.62 ± 8.91 (P = 0.000), mean septal to posterior wall delay 164.30 ± 106.03 ms to 78.13 ± 38.04 ms (P = 0.001), mean interventricular delay 44.47 ± 23.47 ms to 26.72 ± 16.87 ms (P = 0.006), mean mitral regurgitation grade 2.50 ± 0.98 to 1.88 ± 0.90 (P = 0.026) and mean systolic dysfunction grade 3.96 ± 0.20 to 3.31 ± 0.97 (P = 0.001). Conclusion: The improvements in mean NYHA class, ejection fraction and synchrony, at follow-up, were highly significant.



How to cite this article:
Uwanuruochi K, Ganasekar A, Solomon B, Murugesan RK, Krishnamoorthy J, Pandurangi UM. Short-term outcome of cardiac resynchronization carried out at the Madras Medical Mission, India.Nig J Cardiol 2014;11:124-126


How to cite this URL:
Uwanuruochi K, Ganasekar A, Solomon B, Murugesan RK, Krishnamoorthy J, Pandurangi UM. Short-term outcome of cardiac resynchronization carried out at the Madras Medical Mission, India. Nig J Cardiol [serial online] 2014 [cited 2019 Oct 24 ];11:124-126
Available from: http://www.nigjcardiol.org/text.asp?2014/11/2/124/142110


Full Text

 INTRODUCTION



Cardiac resynchronization therapy (CRT) is a relatively new therapy for patients with symptomatic heart failure resulting from systolic dysfunction whereby both the left and right ventricles are simultaneously paced. [1] The procedure resynchronizes the timing of global left ventricular (LV) depolarization and improves mechanical contractility and mitral regurgitation.

It is an accepted recommendation for patients in sinus rhythm with a widened QRS interval (≥150 ms) not due to right bundle branch block who have severe LV systolic dysfunction and persistent New York Heart Association (NYHA) functional Class II-III symptoms despite optimal medical therapy. [2] In addition, CRT is considered reasonable (Class II a) for patients with LV ejection fraction (LVEF) ≤35% with NYHA functional Class III, or ambulatory Class IV symptoms who are receiving optimal medical therapy and who have frequent dependence on ventricular pacing, or are in atrial fibrillation. [3] The reported benefit of CRT has included improvement in functional class, reduced frequency of hospitalization and prolonged survival. [4],[5]

 MATERIALS AND METHODS



This was a retrospective study of CRT carried out at the Madras Medical Mission over the past 5 years. We sought to describe the demographic characteristics of the patients who underwent CRT, the spectrum of indications for CRT in the patients, and the short-term changes in NYHA class, LVEF, hemodynamics and echocardiographic indices of synchrony. We also observed the success rate of the procedure, as well as the frequency of early complications. The data were obtained from the records of the Cardiac Electrophysiology Department.

The following parameters: LVEF, QRS duration, septal to posterior wall delay (SPWD), interventricular delay (IVD), heart rate and systolic blood pressure were compared at baseline and at the most recent follow-up after CRT. The data obtained was analyzed using SPSS statistical software version 15 (SPSS, Inc. Chicago Illinois). Categorical data were compared using the Chi-square-test, while continuous data were compared using t-test. Probability levels of ≤ 0.05 were considered as significant.

 RESULTS



Overall, 55 cases were involved in the review. There were 34 males and 21 females. The mean age was 60.42 ± 10.59 years. The minimum age was 37 years, while the maximum was 85 years.

The underlying diagnoses in the patients were distributed as follows: Idiopathic dilated cardiomyopathy 35 (63.6%), ischemic cardiomyopathy 18 (32.7%), and degenerative valvular heart disease 1 (1.8%) and rheumatic valvular disease 1 (1.8%).

Fourteen patients had complete heart block; two had high-grade AB block, while one had trifascicular block. Left bundle branch block was documented in 35 patients.

Forty patients received biventricular pacemakers. Thirteen patients were place on CRT with defibrillator; the reasons include documented ventricular tachycardia, [6] loss of consciousness, [2] resuscitated cardiac arrest, [2] and increased risk of sudden cardiac death in presence of progressive dyspnea, severe LV dysfunction and left bundle branch block. [3]

The duration between CRT and follow-up varied from a minimum of 2 months to a maximum of 37 months, with a mean interval of 11.32 ± 9.25 months. The changes in the parameters of interest were as described in [Table 1].{Table 1}

Cardiac resynchronization therapy implantation was successful in all patients, but in one patient during LV pacing dyssynchrony increased in spite of intrinsic QRS being narrow and biventricular pacing was avoided by increasing the atrioventricullar delay. Cardiac tamponade resulted in one patient following right ventricular apical perforation during right ventricular lead placement, but the patients stabilized after pericardiocentesis.

In four of the patients, an LV epicardial lead placement at thoracotomy was carried out due to displacement of the endocardial lead in three cases and unsuccessful attempts to cannulate the coronary sinus in one patient. There was no mortality.

 DISCUSSION



The improvement in the mean NYHA class was highly statistically significant when compared with the baseline data. The distribution also compares favorably with that observed by Angelo Auricchio et al. [6] who reviewed patients after 12 months post implantation, comparable to our mean follow-up time of 11.32 ± 8.57 months.

The mean ejection fraction improved from 27.56 ± 5.47 to 38.62 ± 8.91 (P = 0.000) at follow-up. Vaillant et al. [7] who, similarly, reviewed patients after 12 months of CRT observed an improvement in ejection fraction 31% ± 12% to 56% ± 8% (P = 0.027). Our result was more significant because they had fewer patients [6] in their study. The mean mitral regurgitation grade improved from 2.50 ± 0.98 to 1.88 ± 0.90 (P = 0.026). In comparison, Peraldo et al. [8] observed the degree of mitral regurgitation to improve from 1.9 ± 1.0 to 1.3 ± 1.0 after 12 months.

The markers of dyssynchrony also showed significant improvements. The mean QRS reduced from 165.04 ± 13.74 to 121.75 ± 26.56 (P = 0.000). Likewise, the reductions in mean SPWD and IVD were also significant at follow-up. This compares favorably with the report of Peraldo et al., [8] a reduction of QRS duration from 137 ± 19 to 129 ± 16, and change in IVMD from 39 ± 33 to 8 ± 24; both after 12 months of CRT.

 CONCLUSION



The clinical benefit of CRT, as shown by the improvement in mean NYHA class at follow-up, as well as the improvement in ejection fraction was highly significant. There was also echocardiographic evidence of improved synchrony. Cardiac resynchronization has become an established procedure with documented clinical benefit. There is a need to place this option before the patients who meet the indication. There is also a need for health facilities to support trainings in interventional cardiology.

 LIMITATIONS



The data were not designed originally for this analysis, and the study was retrospective. Many cases were excluded at different stages of the analysis; reasons include parameters used to assess dyssynchrony differing before and after CRT, not keeping follow-up appointments and incomplete data records. Many patients also did not keep to appointments at the specified dates, making it difficult to compare benefit across a specific time interval.

 APPRECIATION



The Medical Director of Federal Medical Center Umuahia, Dr. Abali Chuku and the Staff of the Electrophysiology clinical research office of Madras Medical Mission.

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