International Journal of Cardiology 176 (2014) 1137–1138
Contents lists available at ScienceDirect
International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard
Letter to the Editor
Permanent pacemaker utilization in older patients with syncope and carotid sinus syndrome☆ Sahil Khera a,⁎,1, Dhaval Kolte b,1, Sei Iwai a, Chandrasekar Palaniswamy a, Prakash Harikrishnan b, Tanush Gupta b, Marjan Mujib b, Diwakar Jain a, Howard A. Cooper a, Wilbert S. Aronow a, Gregg C. Fonarow c, Julio A. Panza a a b c
Department of Medicine, Division of Cardiology, New York Medical College, Valhalla, NY, United States Department of Medicine, New York Medical College, Valhalla, NY, United States Department of Medicine, Division of Cardiology, University of California at Los Angeles, CA, United States
a r t i c l e
i n f o
Article history: Received 15 July 2014 Accepted 27 July 2014 Available online 13 August 2014 Keywords: Carotid sinus syndrome Syncope Permanent pacemaker
Carotid sinus syndrome (CSS) can be divided into three sub-types based on the blood pressure and heart rate response to carotid sinus massage of 5–10 s. Cardio-inhibitory carotid sinus hypersensitivity is diagnosed by ≥3 to 5-second pause; vasodepressor type based on a reduction in systolic blood pressure by at least 50 mm Hg, and a mixed sub-type carotid sinus hypersensitivity manifested by a combination of the two. CSS is associated with aging and atherosclerosis. Elderly patients commonly present to the hospital with syncope and falls. Presence of CSS is variable and observed in 22% to 68% of older patients with previously undiagnosed syncope [1]. In a series of 352 patients ≥65 years of age at our institute, 2% were diagnosed with CSS and 31% remained undiagnosed on initial evaluation [2]. It is likely that a fraction of elderly patients with undiagnosed syncope have CSS that is not clinically apparent. The 2008 American College of Cardiology/American Heart Association/Heart Rhythm Society guidelines recommend permanent pacemaker (PPM) implantation in patients with recurrent syncope caused by spontaneously occurring carotid sinus stimulation and carotid sinus pressure that induces
☆ Funding: None. ⁎ Corresponding author at: Division of Cardiology, Macy Pavilion, New York Medical College, Valhalla, NY 10595, United States. Tel.: +1 914 564 7587. E-mail address: [email protected] (S. Khera). 1 Sahil Khera, MD and Dhaval Kolte, MD, PhD have contributed equally to this letter.
http://dx.doi.org/10.1016/j.ijcard.2014.07.287 0167-5273/© 2014 Elsevier Ireland Ltd. All rights reserved.
ventricular asystole of N 3 s (Class I C), and in patients with syncope without a clear provocative event but with a hypersensitive carotid response (Class IIa C) [3]. Before determining if pacing is clinically indicated, the contribution of cardioinhibitory and vasodepressor components should be assessed in every patient. Pacing is effective in predominantly cardioinhibitory subtypes than vasodepressor or mixed subtypes and is more effective in prevention of syncopal episodes than presyncope or vague symptoms. The selection of pacing mode is also crucial in the management of patients with cardioinhibitory CSS. There is no role of single-chamber atrial pacing as these patients have higher rates of atrioventricular block. Dual chamber pacing is preferred over single chamber ventricular pacing [4,5]. In this descriptive analysis, we report the permanent pacemaker utilization rates and clinical and baseline characteristics of patients ≥65 years of age presenting to the United States hospitals with a primary diagnosis of syncope and a concomitant diagnosis of carotid sinus syndrome, using the 2009–2010 Nationwide Inpatient Sample (NIS) databases. The NIS, sponsored by the Agency for Healthcare Research and Quality as a part of Healthcare Cost and Utilization Project, is the largest publicly available all-payer inpatient care database in the United States. It contains discharge-level data from approximately 8 million hospital stays from about 1000 hospitals designed to approximate a 20% stratified sample of all community hospitals in the United States. Criteria used for stratified sampling of hospitals include hospital ownership, bed size, teaching status, urban or rural location, and geographic region. Discharge weights are provided for each patient discharge record, which were used to obtain national estimates. Data on demographics, co-morbidities, PPM utilization and pacing mode type were extracted and analyzed using IBM SPSS Statistics 20.0 (IBM Corp., Armonk, NY). All p values were 2-sided with a significance threshold of p b 0.05. Categorical variables are expressed as percentage and continuous variables as mean ± standard deviation. We analyzed the 2009–2010 NIS databases to identify all patients aged ≥ 65 years with the principal diagnosis of syncope (ICD-9-CM code 780.2). Patients with CSS were then identified using ICD-9-CM code 337.01. The type of PPM implanted was characterized as either dual-chamber (DDD), single-chamber ventricular (VVI), singlechamber atrial (AAI), or biventricular (BiV) pacemaker. For the present
1138
S. Khera et al. / International Journal of Cardiology 176 (2014) 1137–1138
study, we used ICD-9-CM procedure codes to identify DDD (37.83), VVI (37.81–82, 37.71), AAI (37.81–82, 37.73), or BiV (00.51) PPM implantation. This approach has been used by other investigators using the NIS database [6]. Of 337,195 patients with a primary diagnosis of syncope, 240 (0.07%) had a concomitant diagnosis of CSS. Patients with CSS had a mean age of 79.5 ± 7.3 years; and were more likely to be white (68.7%) and men (63.8%). None of the patients with CSS had a diagnosis of high-degree atrioventricular, bifascicular or trifascicular block. None of the patients in the CSS group died during hospitalization. Of the 240 patients with CSS, 35% (84/240) underwent PPM implantation (mean age 77.5 ± 8.6 years). PPM utilization rate was higher in women (49.4%) than in men (27.3%), and in whites (41.8%) than in nonwhites (20.8%). Furthermore, use of PPM in CSS was higher in urban hospitals, and in larger hospitals. Dual chamber atrioventricular sequential pacing (DDD mode) was used in all patients with CSS undergoing PPM implantation. Table 1 compares the baseline demographics and co-morbidities of CSS patients with and without PPM implantation. Twelve percent of patients with CSS who underwent PPM placement had a concomitant diagnosis of sick sinus syndrome. The average length of stay was longer in CSS patients undergoing PPM placement (2.9 ± 1.8 versus 2.6 ± 1.6 days, p = 0.003). Patients undergoing PPM implantation also accrued greater mean total hospital charges as compared to those without PPM implantation ($56,038 ± 26,618 versus $16,125 ± 9745, p b 0.001). This study has certain limitations. Since this is a retrospective, observational study, the possibility of selection bias cannot be completely eliminated. NIS is an administrative database and there is the potential for unrecognized miscoding of diagnostic and procedure codes. Clinical presentation variables are not available in this administrative database and hence sub-types of CSS cannot be delineated. It is also not possible to assess if the syncopal episode was first or recurrent. However, these potential limitations may be partially compensated by the large size of the database and the ability to obtain nationwide estimates using the discharge weights provided.
Table 1 Baseline demographic and clinical variables in patients with and without permanent pacemaker (PPM) implantation for syncope and carotid sinus syndrome (N = 240). Variable
No PPM (n = 156)
PPM (n = 84)
p-Value
Age, years Women Race White Non-white Weekend admission Urban location Region Northeast Midwest South West Teaching hospital Hospital bed size Small Medium Large Smoking Dyslipidemia Coronary artery disease Congestive heart failure Diabetes, uncomplicated Diabetes, with complications Hypertension Peripheral vascular disease Chronic kidney disease
80.6 ± 6.2 28.2%
77.5 ± 8.6 50.6%
0.002 0.001
83.5% 16.5% 25.6% 81.6%
93.2% 6.8% 25.0% 94.1%
0.093
25.0% 19.2% 41.0% 14.7% 56.8%
38.1% 19.0% 36.9% 6.0% 42.9%
11.6% 33.6% 54.8% 15.3% 40.1% 27.6% 12.8% 12.8% 12.2% 79.5% 10.2% 21.7%
6.0% 17.9% 76.2% 25.0% 42.9% 36.9% 0% 13.1% 0% 69.0% 5.9% 7.1%
0.913 0.008 0.071
0.041 0.005
0.065 0.681 0.135 0.001 0.952 0.001 0.072 0.256 0.004
In conclusion, carotid sinus syndrome should be considered in the differential diagnosis of elderly patients with syncope or unexplained falls. Permanent pacing is indicated in patients with cardioinhibitory form of CSS who present with recurrent syncope and our study indicates that 35% of older patients with a diagnosis of syncope and concomitant carotid sinus syndrome had PPM implanted. However, the relative contribution of the cardioinhibitory and vasodepressor components to the syncopal episode in each patient needs to be carefully evaluated before considering permanent pacemaker in these patients. Conflicts of interest Dr. Iwai is on a Safety and Data Monitoring Board for BIOTRONIK and Dr. Fonarow has served as a consultant for Medtronic. Other authors have no conflicts of interest to disclose. References [1] Seifer C. Carotid sinus syndrome. Cardiol Clin 2013;31:111–21. [2] Khera S, Palaniswamy C, Aronow WS, et al. Predictors of mortality, rehospitalization for syncope, and cardiac syncope in 352 consecutive elderly patients with syncope. J Am Med Dir Assoc 2013;14:326–30. [3] Epstein AE, DiMarco JP, Ellenbogen KA, et al. American College of Cardiology/ American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices), American Association for Thoracic Surgery, Society of Thoracic Surgeons. ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/ American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices) developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons. J Am Coll Cardiol 2008;51:e1-62. [4] Brignole M, Menozzi C. The natural history of carotid sinus syncope and the effect of cardiac pacing. Europace 2011;13:462–4. [5] Lopes R, Gonçalves A, Campos J, et al. The role of pacemaker in hypersensitive carotid sinus syndrome. Europace 2011;13:572–5. [6] Greenspon AJ, Patel JD, Lau E, et al. 16-year trends in the infection burden for pacemakers and implantable cardioverter-defibrillators in the United States: 1993 to 2008. J Am Coll Cardiol 2011;58:1001–6.
Contents lists available at ScienceDirect
International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard
Letter to the Editor
Permanent pacemaker utilization in older patients with syncope and carotid sinus syndrome☆ Sahil Khera a,⁎,1, Dhaval Kolte b,1, Sei Iwai a, Chandrasekar Palaniswamy a, Prakash Harikrishnan b, Tanush Gupta b, Marjan Mujib b, Diwakar Jain a, Howard A. Cooper a, Wilbert S. Aronow a, Gregg C. Fonarow c, Julio A. Panza a a b c
Department of Medicine, Division of Cardiology, New York Medical College, Valhalla, NY, United States Department of Medicine, New York Medical College, Valhalla, NY, United States Department of Medicine, Division of Cardiology, University of California at Los Angeles, CA, United States
a r t i c l e
i n f o
Article history: Received 15 July 2014 Accepted 27 July 2014 Available online 13 August 2014 Keywords: Carotid sinus syndrome Syncope Permanent pacemaker
Carotid sinus syndrome (CSS) can be divided into three sub-types based on the blood pressure and heart rate response to carotid sinus massage of 5–10 s. Cardio-inhibitory carotid sinus hypersensitivity is diagnosed by ≥3 to 5-second pause; vasodepressor type based on a reduction in systolic blood pressure by at least 50 mm Hg, and a mixed sub-type carotid sinus hypersensitivity manifested by a combination of the two. CSS is associated with aging and atherosclerosis. Elderly patients commonly present to the hospital with syncope and falls. Presence of CSS is variable and observed in 22% to 68% of older patients with previously undiagnosed syncope [1]. In a series of 352 patients ≥65 years of age at our institute, 2% were diagnosed with CSS and 31% remained undiagnosed on initial evaluation [2]. It is likely that a fraction of elderly patients with undiagnosed syncope have CSS that is not clinically apparent. The 2008 American College of Cardiology/American Heart Association/Heart Rhythm Society guidelines recommend permanent pacemaker (PPM) implantation in patients with recurrent syncope caused by spontaneously occurring carotid sinus stimulation and carotid sinus pressure that induces
☆ Funding: None. ⁎ Corresponding author at: Division of Cardiology, Macy Pavilion, New York Medical College, Valhalla, NY 10595, United States. Tel.: +1 914 564 7587. E-mail address: [email protected] (S. Khera). 1 Sahil Khera, MD and Dhaval Kolte, MD, PhD have contributed equally to this letter.
http://dx.doi.org/10.1016/j.ijcard.2014.07.287 0167-5273/© 2014 Elsevier Ireland Ltd. All rights reserved.
ventricular asystole of N 3 s (Class I C), and in patients with syncope without a clear provocative event but with a hypersensitive carotid response (Class IIa C) [3]. Before determining if pacing is clinically indicated, the contribution of cardioinhibitory and vasodepressor components should be assessed in every patient. Pacing is effective in predominantly cardioinhibitory subtypes than vasodepressor or mixed subtypes and is more effective in prevention of syncopal episodes than presyncope or vague symptoms. The selection of pacing mode is also crucial in the management of patients with cardioinhibitory CSS. There is no role of single-chamber atrial pacing as these patients have higher rates of atrioventricular block. Dual chamber pacing is preferred over single chamber ventricular pacing [4,5]. In this descriptive analysis, we report the permanent pacemaker utilization rates and clinical and baseline characteristics of patients ≥65 years of age presenting to the United States hospitals with a primary diagnosis of syncope and a concomitant diagnosis of carotid sinus syndrome, using the 2009–2010 Nationwide Inpatient Sample (NIS) databases. The NIS, sponsored by the Agency for Healthcare Research and Quality as a part of Healthcare Cost and Utilization Project, is the largest publicly available all-payer inpatient care database in the United States. It contains discharge-level data from approximately 8 million hospital stays from about 1000 hospitals designed to approximate a 20% stratified sample of all community hospitals in the United States. Criteria used for stratified sampling of hospitals include hospital ownership, bed size, teaching status, urban or rural location, and geographic region. Discharge weights are provided for each patient discharge record, which were used to obtain national estimates. Data on demographics, co-morbidities, PPM utilization and pacing mode type were extracted and analyzed using IBM SPSS Statistics 20.0 (IBM Corp., Armonk, NY). All p values were 2-sided with a significance threshold of p b 0.05. Categorical variables are expressed as percentage and continuous variables as mean ± standard deviation. We analyzed the 2009–2010 NIS databases to identify all patients aged ≥ 65 years with the principal diagnosis of syncope (ICD-9-CM code 780.2). Patients with CSS were then identified using ICD-9-CM code 337.01. The type of PPM implanted was characterized as either dual-chamber (DDD), single-chamber ventricular (VVI), singlechamber atrial (AAI), or biventricular (BiV) pacemaker. For the present
1138
S. Khera et al. / International Journal of Cardiology 176 (2014) 1137–1138
study, we used ICD-9-CM procedure codes to identify DDD (37.83), VVI (37.81–82, 37.71), AAI (37.81–82, 37.73), or BiV (00.51) PPM implantation. This approach has been used by other investigators using the NIS database [6]. Of 337,195 patients with a primary diagnosis of syncope, 240 (0.07%) had a concomitant diagnosis of CSS. Patients with CSS had a mean age of 79.5 ± 7.3 years; and were more likely to be white (68.7%) and men (63.8%). None of the patients with CSS had a diagnosis of high-degree atrioventricular, bifascicular or trifascicular block. None of the patients in the CSS group died during hospitalization. Of the 240 patients with CSS, 35% (84/240) underwent PPM implantation (mean age 77.5 ± 8.6 years). PPM utilization rate was higher in women (49.4%) than in men (27.3%), and in whites (41.8%) than in nonwhites (20.8%). Furthermore, use of PPM in CSS was higher in urban hospitals, and in larger hospitals. Dual chamber atrioventricular sequential pacing (DDD mode) was used in all patients with CSS undergoing PPM implantation. Table 1 compares the baseline demographics and co-morbidities of CSS patients with and without PPM implantation. Twelve percent of patients with CSS who underwent PPM placement had a concomitant diagnosis of sick sinus syndrome. The average length of stay was longer in CSS patients undergoing PPM placement (2.9 ± 1.8 versus 2.6 ± 1.6 days, p = 0.003). Patients undergoing PPM implantation also accrued greater mean total hospital charges as compared to those without PPM implantation ($56,038 ± 26,618 versus $16,125 ± 9745, p b 0.001). This study has certain limitations. Since this is a retrospective, observational study, the possibility of selection bias cannot be completely eliminated. NIS is an administrative database and there is the potential for unrecognized miscoding of diagnostic and procedure codes. Clinical presentation variables are not available in this administrative database and hence sub-types of CSS cannot be delineated. It is also not possible to assess if the syncopal episode was first or recurrent. However, these potential limitations may be partially compensated by the large size of the database and the ability to obtain nationwide estimates using the discharge weights provided.
Table 1 Baseline demographic and clinical variables in patients with and without permanent pacemaker (PPM) implantation for syncope and carotid sinus syndrome (N = 240). Variable
No PPM (n = 156)
PPM (n = 84)
p-Value
Age, years Women Race White Non-white Weekend admission Urban location Region Northeast Midwest South West Teaching hospital Hospital bed size Small Medium Large Smoking Dyslipidemia Coronary artery disease Congestive heart failure Diabetes, uncomplicated Diabetes, with complications Hypertension Peripheral vascular disease Chronic kidney disease
80.6 ± 6.2 28.2%
77.5 ± 8.6 50.6%
0.002 0.001
83.5% 16.5% 25.6% 81.6%
93.2% 6.8% 25.0% 94.1%
0.093
25.0% 19.2% 41.0% 14.7% 56.8%
38.1% 19.0% 36.9% 6.0% 42.9%
11.6% 33.6% 54.8% 15.3% 40.1% 27.6% 12.8% 12.8% 12.2% 79.5% 10.2% 21.7%
6.0% 17.9% 76.2% 25.0% 42.9% 36.9% 0% 13.1% 0% 69.0% 5.9% 7.1%
0.913 0.008 0.071
0.041 0.005
0.065 0.681 0.135 0.001 0.952 0.001 0.072 0.256 0.004
In conclusion, carotid sinus syndrome should be considered in the differential diagnosis of elderly patients with syncope or unexplained falls. Permanent pacing is indicated in patients with cardioinhibitory form of CSS who present with recurrent syncope and our study indicates that 35% of older patients with a diagnosis of syncope and concomitant carotid sinus syndrome had PPM implanted. However, the relative contribution of the cardioinhibitory and vasodepressor components to the syncopal episode in each patient needs to be carefully evaluated before considering permanent pacemaker in these patients. Conflicts of interest Dr. Iwai is on a Safety and Data Monitoring Board for BIOTRONIK and Dr. Fonarow has served as a consultant for Medtronic. Other authors have no conflicts of interest to disclose. References [1] Seifer C. Carotid sinus syndrome. Cardiol Clin 2013;31:111–21. [2] Khera S, Palaniswamy C, Aronow WS, et al. Predictors of mortality, rehospitalization for syncope, and cardiac syncope in 352 consecutive elderly patients with syncope. J Am Med Dir Assoc 2013;14:326–30. [3] Epstein AE, DiMarco JP, Ellenbogen KA, et al. American College of Cardiology/ American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices), American Association for Thoracic Surgery, Society of Thoracic Surgeons. ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: a report of the American College of Cardiology/ American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices) developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons. J Am Coll Cardiol 2008;51:e1-62. [4] Brignole M, Menozzi C. The natural history of carotid sinus syncope and the effect of cardiac pacing. Europace 2011;13:462–4. [5] Lopes R, Gonçalves A, Campos J, et al. The role of pacemaker in hypersensitive carotid sinus syndrome. Europace 2011;13:572–5. [6] Greenspon AJ, Patel JD, Lau E, et al. 16-year trends in the infection burden for pacemakers and implantable cardioverter-defibrillators in the United States: 1993 to 2008. J Am Coll Cardiol 2011;58:1001–6.
