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 Table of Contents  
ORIGINAL ARTICLE
Year : 2020  |  Volume : 17  |  Issue : 2  |  Page : 136-141

Experience with cardiac pacing in the Nigerian Delta region


1 Department of Cardiology, Bayelsa Specialist Hospital, Yenagoa; Department of Internal Medicine, University of Port Harcourt Teaching Hospital, Port Harcourt, Nigeria
2 Department of Internal Medicine, University of Port Harcourt Teaching Hospital, Port Harcourt, Nigeria
3 Department of Cardiology, Bayelsa Specialist Hospital, Yenagoa, Nigeria

Date of Submission25-Oct-2019
Date of Decision09-Jan-2020
Date of Acceptance18-Jun-2020
Date of Web Publication13-Nov-2021

Correspondence Address:
Dr. Emmanuel Auchi Edafe
Bayelsa Specialist Hospistal, Yenagoa
Nigeria
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/njc.njc_28_19

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  Abstract 


Introduction: Pacemaker implantation is an important intervention that has been shown to improve the quality of life and reduce mortality in patients with bradyarrhythmias. The objective of this study was to report the permanent cardiac pacing at the Bayelsa Specialist Hospital between June 1, 2017, and May 31, 2019, with the indications, pacemaker type, methods, and complications.
Methods: This was a retrospective descriptive study of 44 adult patients with permanent cardiac pacing. Medical records of all patients who had permanent pacing between June 1, 2017, and May 31, 2019, were collected.
Results: A total of 44 patients were treated. The age range was from 15 to 98 years with a median of 74.00 years. There were 25 (56.8%) males and 19 (43.2%) females. The major symptoms were syncope 20 (45.5%), dizziness and syncope 10 (22.7%), and palpitation and syncope 6 (13.6%). The most common electrocardiography finding was complete heart block (CHB) in 31 patients (70.46%). Four patients had single-chamber pacing (VVIR), 40 (90.9%) had dual-chamber pacing, and three had ventricular lead extraction and re-implantation of a new lead. Twenty-nine patients had apical pacing and 15 received septal pacing and all the leads were bipolar.
Conclusion: CHB was the most common reason for pacemaker implantation and dual chamber was the preferred technique because it mimics the natural atrioventricular synchronization of the sinus rhythm in normal subjects.

Keywords: Bipolar lead, dual chamber, pacemaker


How to cite this article:
Edafe EA, Odia JO, Akpa MR, Dodiyi-Manual ST, Oye H, Agadah Z. Experience with cardiac pacing in the Nigerian Delta region. Nig J Cardiol 2020;17:136-41

How to cite this URL:
Edafe EA, Odia JO, Akpa MR, Dodiyi-Manual ST, Oye H, Agadah Z. Experience with cardiac pacing in the Nigerian Delta region. Nig J Cardiol [serial online] 2020 [cited 2021 Dec 5];17:136-41. Available from: https://www.nigjcardiol.org/text.asp?2020/17/2/136/330425




  Introduction Top


There has been an increasing growth in the number of implantations in the Niger Delta region. This is due to the increased number of cardiac catheterization and trained interventional cardiologists with capabilities of cardiac device implantation.

Cardiac pacing is a life-saving procedure in patients with symptomatic bradycardia. Sinus anode dysfunction is the cause of symptomatic bradycardia in 50% of the patients from western literatures.[1],[2],[3] Whether this trend is the same in Nigeria remains to be extensively study. Patients with symptomatic bradycardia may present with syncope, presyncopal, dizziness, palpitation, etc., They are at risk of developing heart failure and sudden death due to prolonged asystole or ventricular arrhythmia.[4] Artificial pacemakers are used in the management of symptomatic bradycardia. This improves the hemodynamic state of such patients.[5] These devices are expensive and are not without complications such as lead fracture, dislodgment, perforation, and venous thromoembolism.[6],[7]

The objective of this study was to evaluate permanent cardiac pacing in a referral hospital in the Niger Delta region of Nigeria over a 2 year period (June 1, 2017–May 31, 2019). The specific objectives were to describe the indications for cardiac pacing, pacemaker types, methods, and complications.


  Methods Top


This was a retrospective descriptive study. We examined the medical records of all patients referred to the cardiovascular center of the Bayelsa Specialist Hospital, Yenagoa. The hospital has sixty beds, eight of which are in the intensive care unit. The cardiovascular center has one cardiac catheterization room with a general electric (GE) optimal image intensifier used for angiography and angioplasty. Another room with a GE C-arm is used for the pacemaker implantation. The C-arm room is also equipped with one temporary pacemaker implantation and a complete set of radiation protection equipment. Records of all patients treated between June 1, 2017, and May 31, 2019, were examined. Data extracted included patients demographics, clinical parameters, indications for pacing, device types, and outcomes.

Inclusion criteria

All patients with symptomatic bradycardia needing permanent transvenous pacemakers in the period under review were included in the study.

Exclusion criteria

Patients with asymptomatic bradycardia and patients who received temporary pacemakers were excluded from the study.

Data analysis

Statistical analysis was performed using the 20th version of Statistical Package for the Social Sciences, IBM cooperation 2011, Armonk, New York, USA. The results were presented in tabular or graphical forms, as were appropriate.

Definition of terms

  1. Sinus bradycardia: Sinus rate <50 bpm.[8] Symptomatic bradycardia could present with the following: dizziness, confusion, palpitations, breathlessness, exercise intolerance, and syncope (blackout or fainting) or presyncope[8]
  2. Sinus pause: Sinus node depolarizes >3 s after the last atrial depolarization[8]
  3. Sinus node arrest: No evidence of sinus node depolarization[8]
  4. Tachycardia–bradycardia (“tachy-brady”) syndrome: Sinus bradycardia, ectopic atrial bradycardia or sinus pause alternating with periods of abnormal atrial tachycardia, atrial flutter, or atrial fibrillation. The tachycardia may be associated with suppression of sinus node automaticity and a sinus pause of variable duration when the tachycardia terminates[8]
  5. Mobitz Type I: P-waves with a constant rate (<100 bpm) with a periodic single nonconducted P-wave associated with P waves before and after the nonconducted P wave with inconstant PR intervals[8]
  6. Mobitz Type II: P-waves with a constant rate (<100 bpm) with a periodic single nonconducted P-wave associated with other P-waves before and after the nonconducted P wave with constant PR intervals (excluding 2:1 atrioventricular [AV] block)[8]
  7. Third-degree AV block (complete heart block [CHB]): AV dissociation[8]
  8. Diabetes mellitus: A patient is said to be diabetic when the random blood glucose is ≥11.1 mmol/l (200 mg/dl) or fasting plasma glucose ≥7.0 mmol/l (126 mg/dl) or on antidiabetic medications.[9] In the absence of unequivocal hyperglycemia and acute metabolic decompensation, these criteria are confirmed by repeat testing on a different day[9]
  9. Hypertension: A patient is hypertensive when the systolic and diastolic blood pressure is persistently equal to or more than 140/90 mmHg or on antihypertensive medications[10]
  10. Ischemic heart disease: Ischemic heart disease occurs when a patient has a symptom, sign, or complication of inadequate blood supply to the myocardium or a known document coronary artery disease patient on medication[11]
  11. Dual-chamber pacemaker: This is a pacemaker with two leads to two chambers of the heart. The patient has one lead to the right atrium and the other to the right ventricle
  12. Single-chamber pacemaker: This is a pacemaker with one lead to a chamber of the heart. The patient has one lead to the right atrium or ventricle
  13. Septal pacing: The pacemaker is screwed to the septum
  14. Apical pacing: The pacemaker lead is screwed or anchor to the right ventricular (RV) apex
  15. Bipolar leads: This is a lead that has the cathode and anode toward the end of the lead wire. Current flows from the lead tip, stimulates the heart, and returns to the anode just above the tip
  16. Magnetic resonance imaging (MRI)-conditioned pacemaker: MRI-conditioned pacing system is a pacemaker designed to allow an implanted pacemaker patient to undergo MRI scan under specified MRI conditions for use.



  Results Top


A total of 44 patients were treated during the period. The age range was from 15 to 98 years with a median of 74.00 years. There were 25 males (56.8%) and 19 females (43.2%). The age distribution is shown in [Table 1]. The waiting time before pacemaker implantation ranges from 2 to 20 weeks. This was to enable patients and families to get the needed finance for the procedure. It also depends on the frequency of symptoms. The patient's family and extended relatives contribute more quickly for the patient with more frequent symptoms.
Table 1: Demographic profile of pacemaker patients

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Twenty patients were hypertensive, 15 had diabetes mellitus plus hypertension, and 9 had ischemic heart disease [Figure 1]. The presenting symptoms were syncopal attacks in 20 (45.5%) patients, syncope plus dizziness in 10 (22.7%), syncope plus light headedness in 4 (9%), syncope and palpitation in 6 (13.6%), presyncope in 3 (6.8%), and nausea with vomiting in 1 (2.3%) [Figure 2].
Figure 1: Cardiovascular risk factors among subjects (n=44)

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Figure 2: Presenting complaints among the subjects (n = 44)

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CHB was seen in 31 patients (70.5%), atrial fibrillation with CHB in 4 patients (9.1%), sick sinus node disease with CHB in 4 patients (9.1%), Mobitz Type 2 in 3 patients (6.8%), and 2:1 block in 2 patients (4.5%). This is shown in [Figure 3]. Pacemaker types implanted were 4 (9.10%) single-chamber and 40 (90.90) dual-chamber device [Figure 4].
Figure 3: Electrocardiographic diagnosis among the subjects

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Figure 4: Implantation procedure (n = 44)

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Right subclavian access was used in 3 (6.8%) and left subclavian access in 41 (93.2%) patients. Thirty-nine (88.6%) patients had <2 attempts before venous access was gained [Figure 5].
Figure 5: Procedure-related features

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Three patients (6.8%) had a pulse generator MRI-conditioned pacemaker. Fifteen patients (34.1%) had septal lead pacing. All leads were bipolar [Figure 6]. Of the 44 patients, one had lead dislodgment. This was noticed on the 2nd day postimplantation. The patient was taken to the laboratory for reposition [Figure 7] and [Figure 8]. One patient had implant pocket infection requiring implant replacement on the right side.
Figure 6: Pulse generator and lead characteristics

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Figure 7: Before taking out the right ventricular dislodged lead and repositioning

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Figure 8: After taking out the dislodged lead and re-positioned right ventricular lead

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  Discussion Top


Transvenous cardiac pacemaker implantation is the treatment of choice for symptomatic bradycardia.[12],[13] Cardiac pacemakers are grouped into the dual and single chamber pacemakers depending on the number of right heart chambers paced.[12],[13] The implantation of pacemakers relieves the symptoms of bradycardia and improves mortality.[14] The four patients with chronic atrial fibrillation had VVIR, while the other forty patients had DDIR pacemaker. The VVI/VVIR pacing is indicated for patients with chronic atrial arrhythmias that are not expected to return to sinus rhythm.[15] The four single chambers were used for the patient with atrial fibrillation with CHB. Two patients were on dabigatran. It was withheld 24 h before the procedure. One patient was on warfarin which was stopped and procedure done at an international normalized ratio (INR) of 2. One patient had the procedure done why on warfarin because INR was 1.0.

The DDD/DDIR/DDDR pacing is the preferred option in patients with AV block.[15] Several of these patients have sinus node dysfunction (intrinsic or drug induced), and so a rate-responsive DDDR option is superior.[15] Some patients may go onto develop striatonigral degeneration later on as they age, and a DDDR pacing is of advantage in the long run.[15] In our study, 40 patients had DDIR pacemaker. Of the forty patients with DDIR, 31 had CHB, sick sinus diseases with CHB were 4, Mobitz type 2 were 3 and high Grade 2:1 block were 2 patients.

The most common transvenous route is the left subclavian vein entered at the junction of the middle and inner thirds where the first rib and the clavicle are joined.[16] Our study showed that right subclavian access was used in 3 (6.8%) and left subclavian access in 41 (93.2%) patients. The reason may include the following: (1) left subclavian access offers easier anatomy for right ventricle lead implant. (2) In case of future upgrade of device to cardiac re-synchronization therapy, the left subclavian access offers easier access for the placement of left ventricular lead. (3) Forty-four patients in this study were right handed. Of three patients with right subclavian, two have abnormal left subclavian vein anatomy and one had pocket infection on the left.

Increasing age is a risk factor for bradycardia. Studies have shown that increasing age is a an independent risk factor for the development of bradycardia.[17],[18] In our study, most of the patients who received pacemaker are above the age of 60 years with a median age of 74 years. This was similar to the age reported by Falase et al. who reported 51 patients with pacemaker implantation and a mean age of 68.2 years.[19] Our report was also similar to that of University of Nigerian Teaching Hospital who reported 23 patients with pacemaker implantation between 2001 and 2006 with a mean age of 70 years.[20] The age range of our patients was from 15 to 98 years. This was similar to the Lagos study that reported a 5-year experience of permanent pacemaker implantation at a Nigerian Teaching Hospital with an age range from 22 to 92 years.[19]

Comorbidities such as diabetes mellitus, hypertension, and ischemic heart disease are seen in patients with symptomatic bradycardia.[21] Barrett et al. noted that hypertension, ischemic heart disease, diabetes mellitus, smoking, and congenital heart disease are risks for the development bradycardia.[18] In our study, there were associated comorbidities such as diabetes mellitus (21%), ischemic heart disease (22.7%), and hypertension (54.8%). This was similar to Kane et al. in the evaluation of cardiac pacing challenge in Sub-Saharan Africa environment in Dakar where 79% and 24% of their patients were hypertensive and diabetic, respectively.[22] The reason for this similarity could be that both the studies were hospital-based studies carried out in sub-Saharan Africa. These risk factors could contribute to a disruption of the electrical impulses associated with bradycardia.[18],[22]

Kane et al. reported that 85% of their patients presented with syncope, vertigo, and dyspnea.[22] Our study showed that presenting symptoms were syncopal attacks in 20 (45.5%) patients, syncope plus dizziness in 10 (22.7%), syncope plus light headedness in 4 (9%), syncope and palpitation in 6 (13.6%), presyncope in 3 (6.8%), and nausea with vomiting in 1 (2.3%). Our result was similar to Falase et al. who evaluated 51 pacemaker patients and reported syncopal attacks in 25 patients (49%) and dizzy spells in 15 patients (29.4%).[19] This similarity may be due to number of patients in the two studies. Furthermore, the two studies were from Nigeria.

Our study reported CHB in 31 patients (70.5%), atrial fibrillation with CHB in 4 patients (9.1%), sick sinus node disease with CHB in 4 patients (9.1%), Mobitz type 2 in 3 patients (6.8%), and 2:1 block in 2 patients (4.5%). This was similar to the report by Falase et al. who reported that electrocardiography diagnosis was CHB in 27 patients (53%), second-degree heart block in 19 patients (37.2%), and sick sinus syndrome (SSS) with bradycardia in 5 patients (9.8%).[19] Adeoye et al. at the University College Hospital Ibadan reported pacemaker implantation.[23] They reported that 39 patients (78%) had CHB, 5 (10%) had Type 2 atrio-ventricular degree block (2HB), 4 (8%) had SSS, and 2 (4%) had trifascicular block were the series of pacemaker implantation.[1] The differences could be in the race and the geographic location of the study.

In our hospital, dual-chamber pacing (90.9%) was more commonly used than single ventricular pacing (9.1%). This was contrary to the report of Falase et al. in Lagos who implanted single chambers in 56.8% of their patients.[19] Adeoye et al. in Ibadan reported single chamber in 49 (98%) of their patients.[23] Kane et al. in Dakar implanted single chamber in 56% of cases and double chamber in 44% of their cases.[22] The reasons for these differences may be due to the following: availability of the single-chamber device, cost, and conveniences of the operation. It takes less time to implant single chamber compared to dual-chamber pacing.

Current prospective randomized controlled trial findings showed no statistically significant difference in death and stroke between DDDR versus VVIR pacing. These studies included the Mode Selection Tria (MOST) and the Canadian Trial of Physiological Pacing (CTOPP).[24],[25] MOST DDDR versus VVIR and the CTOPP (DDD [R] vs. AAI [R] or VVIR) showed no statistically significant difference between VVIR and DDDR in terms of stroke or death.[24],[25] There were also fewer patients with atrial fibrillation in the atrial pacing group.

Left subclavian access was done in 93.2% of our patients. Venous access is basically dependent on operator preference. MRI nonconditioned was used in 93.2% of our patients. These trends were also seen in reports from Ibadan, Lagos, and Dakar. About 34.1% of our patients benefited from septal pacing. The traditional RV lead placement is apical pacing. Septal pacing is a growing technique in Nigeria.


  Conclusion Top


Cardiac pacing is beneficial in the management of bradyarrhythmias. It is available in several centers in Nigeria. Early referral of patients and involvement of the health insurance scheme would make it more accessible.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient (s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

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Tracy CM, Epstein AE, Darbar D, DiMarco JP, Dunbar SB, Estes NR, et al. 2012 ACCF/AHA/HRS focused update of the 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society. Circulation 2012;126:1784-800.  Back to cited text no. 5
    
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Kusumoto FM, Schoenfeld MH, Barrett C, Edgerton JR, Ellenbogen KA, Gold MR, et al. 2018 Guideline on the Evaluation and Management of Patients With Bradycardia and Cardiac Conduction Delay. A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines, and the Heart Rhythm Society. J Am Coll Cardiol 2018;140:382-482.  Back to cited text no. 8
    
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Madershahian N, Scherner M, Weber C, Kuhn E, Choi YH, Slottosch I, et al. Temporary biventricular pacing improves bypass graft flows in coronary artery bypass graft patients with permanent atrial fibrillation. Interact Cardiovasc Thorac Surg 2015;21:435-40.  Back to cited text no. 14
    
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Kane A, Sarr SA, Ndobo JV, Tabane A, Babaka K, Aw F, et al. Cardiac pacing challenge in Sub-Saharan Africa environnement: Experience of the Cardiology Department of Teaching Hospital Aristide Le Dantec in Dakar. BMC Cardiovasc Disord 2019;19:1-7.  Back to cited text no. 22
    
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Adeoye PO, Okonta KE, Salami MA, Adegboye VO. Experience with permanent pacemaker insertion at the University College Hospital, Ibadan, Nigeria. N J Chem 2013;10:1-5.  Back to cited text no. 23
    
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Lamas GA, Lee KL, Sweeney MO, Silverman R, Leon A, Yee R, et al. Ventricular pacing or dual-chamber pacing for sinus-node dysfunction. N Engl J Med 2002;346:1854-62.  Back to cited text no. 24
    
25.
Connolly SJ, Kerr CR, Gent M, Roberts RS, Yusuf S, Gillis AM, et al. Effects of physiologic pacing versus ventricular pacing on the risk of stroke and death due to cardiovascular causes. Canadian trial of physiologic pacing investigators. N Engl J Med 2000;342:1385-91.  Back to cited text no. 25
    


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