Download Spring 2016: Multimodal Management of Atrial Fibrillation

USC CardioVascular Thoracic Institute
recent
accomplishments
Recent publications by our faculty
members include:
THE LEADING EDGE
• Eisenberg EE, Carlson SK, Doshi RN, Shinbane
JS, Chang PM, Saxon LA. Chronic ambulatory
monitoring: results of a large single center
experience. J Innovations Cardiac Rhythm
Management. 2014;5:1818-23.
• Physicians of the CardioVascular Thoracic • Cao M, Chang P, Garon B, Shinbane
Institute hold appointments to national
JS. Cardiac resynchronization therapy:
steering committees developing clinical
double cannulation approach to coronary
practice guidelines13, lead national
venous lead placement via a prominent
• Haberman ZC, Jahn RT, Bose R, et al.
scientific sessions and serve on the
thebesian valve. Pacing Clin Electrophysiol.
Wireless smartphone ECG enables large scale
editorial boards of peer-reviewed journals 2013;36(3):e70-73.
screening in diverse populations. J Cardiovasc
including Journal of Interventional
Electrophysiol 2015 May; 26(5):520-6.
• Carlson SK, Doshi RN. Device therapy
Cardiology, Journal of Cardiovascular
for acute systolic heart failure and atrial
• Konecny T, Friedman PA, Sanon S, Rihal
Electrophysiology, and Vascular Disease
fibrillation. Card Electrophysiology Clin.
CS, Mulpuru SK. Percutaneous trans-apical
Management.
2015;7(3):469-477.
access with closure for ventricular tachycardia
• CVTI physicians have given invited talks at • Cesario D, Powell BD, Roosevelt G, et al. The
ablation. Circ Arrhythm Electrophysiol.
recent meetings of South by Southwest,
role of atrial fibrillation in CRT-D patients: the 2015;8(2):508-511.
BIO International Convention, TEDMed,
ALTITUDE study group. J Innovations Cardiac • Reddy VY, Exner DV, Cantillon DJ, et al.
Wired Health UK, Heart Rhythm Society,
Rhythm Management. 2015;6;1873-80.
Percutaneous implantation of an entirely
American College of Cardiology and at
intracardiac
leadless pacemaker. N Engl J
• Chang PM, Doshi R, Saxon LA. Subcutaneous
numerous medical centers across the
Med.
2015;373(12):1125-1135.
implantable cardioverter-defibrillator.
United States.
Circulation. 2014;129(23):e644-646.
USC CardioVascular Thoracic Institute
To refer a patient to the USC CardioVascular Institute, call: (323) 442-5849
THE
LEADING
EDGE
spring 2016
© 2016 Keck Medicine of USC (16-01-1535 • 2/16)
Multimodal Management of Atrial Fibrillation
The CardioVascular Thoracic Institute at
Keck Medicine of USC offers a multimodal approach to treat patients with
cardiac electrophysiological conditions,
including atrial fibrillation. At the
CardioVascular Thoracic Institute (CVTI),
teams of physicians and surgeons
collaborate across specialties including
electrophysiology, interventional cardiology,
cardiothoracic surgery, pulmonary medicine
and cardiac radiology. We combine and
stage procedures according to the needs of
the patient to deliver the most effective care
for their condition.
Advances in technology have yielded
a broad range of tools to diagnose and
monitor cardiovascular and arrhythmic
conditions. The Center for Body
Computing (CBC) at USC and the
CardioVascular Thoracic Institute have a
robust collaboration that has resulted in
cardiac monitors in the form of wearable
sensors, disposable monitors, implantable
sensors and smartphone monitors with apps.
These sensors are being used to monitor
patients with atrial fibrillation who had
a cryptogenic stroke. CBC is using the
AliveCor smartphone sensor and a unique
app developed to monitor patients with
atrial fibrillation in the peri-ablation period.
CBC and CVTI have also collaborated on
studies for the CardioMEMS device, which
measures pulmonary artery hemodynamics,
and the left atrial pressure sensor (being
investigated in the LAPTOP-HF trial).
CVTI is employing techniques to reduce
the amount of radiation received by patients
who are undergoing electrophysiological
tests and treatments, including catheter
ablations for patients with atrial
fibrillation, ventricular tachycardia and
atrial flutter. Advanced 3-dimensional
imaging technologies (cardiovascular
computed tomography and cardiovascular
magnetic resonance) are used at CVTI to
diagnose anatomic substrates associated
with electrophysiologic disease processes
and guide therapeutic interventions.
See Multimodal Management, page 3
Clinical Trials
The CardioVascular Thoracic Institute
has dedicated research coordinators
to evaluate patients, discuss trial
participation and enroll patients in
clinical trials. Physicians at CVTI are
leading or participating in numerous
clinical trials related to cardiac
electrophysiology.
CVTI has created a prospective,
longitudinal registry to track acute
and chronic outcomes of surgical
and electrophysiologic procedures
performed at Keck Medical Center of
USC aimed at curing atrial fibrillation.
This goal of the registry is to develop
a comprehensive model of care that
utilizes the expertise, coordination
and collaboration of care from
physicians specializing in cardiac
surgery and cardiac electrophysiology.
Another CVTI registry is examining
whether detailed anatomic and
physiologic parameters visualized
with cardiac MRI or cardiac CT
correlate with other modalities
See Clinical Trials, page 6
(855) USC-BEDS (855-872-2337)
For emergent cardiac transfers to
Keck Hospital of USC, call:
cvti.KeckMedicine.org
Or visit:
(323) 442-5849
For more information, call the
USC CardioVascular Thoracic Institute at:
SST-2830, 2011 N. Soto St.
Los Angeles, CA 90032
Health System Marketing and Communications
NONPROFIT ORG
U.S. Postage
PAID
University of
Southern
California
Message from
LEADERSHIP
Dear Colleague,
The field of cardiac electrophysiology involves the evaluation and
treatment of cardiac arrhythmias. At USC, we have assembled an
impressive group of national leaders in the treatment of arrhythmias.
Most prevalent among these arrhythmias is atrial fibrillation which
affects millions of Americans annually. When atrial fibrillation catheter
ablation is an appropriate therapy, USC brings to bear the most talented
group of ablation experts in Southern California with one of the largest
volume clinical programs. The very latest in computerized mapping and
ablation techniques are available at the Keck Medical Center of USC and
are expertly applied.
Ray V. Matthews, MD
Professor of Clinical Medicine
Chief, Cardiovascular Medicine
Keck School of Medicine of USC
An accompanying concern with atrial fibrillation is its propensity to
increase the risk of stroke. Typically, reducing the risk for stroke requires
anticoagulants but USC physicians are leaders in the application of a
procedural technology obviating the need for life-long anticoagulation.
In order to appropriately employ these technologies, the very best
in cardiac imaging is required. USC has a robust program of cardiac
imaging, including the latest CT scan and MRI hardware available.
When a patient’s cardiac condition requires a permanent pacemaker
or implantable cardioverter defibrillator, USC physicians are leaders in
the advancement of this technology. Conventional defibrillators and
biventricular implants are performed with a high degree of expertise.
USC has also been a pioneer in the clinical investigation of implantable
defibrillators not requiring intracardiac leads. These can be especially
useful in patients who are prone to infection. Similarly, a totally
leadless intracardiac pacemaker can now be implanted inside the
heart without any subcutaneous pacemaker required. These and other
technological advances are only a small sample of the expertise in our
electrophysiology program.
Cardiac electrophysiology perhaps best exemplifies the marriage
of technology and clinical treatment of cardiovascular disease. We
welcome the opportunity to partner with you in the care of your patients.
2
USC CardioVascular Thoracic Institute
THE LEADING EDGE
Multimodal Management of Atrial Fibrillation
Continued from page 1
These modalities visualize cardiac and
vascular structures important to cardiac
electrophysiology, including the cardiac
veins, coronary arteries, pulmonary
veins, atrial appendage, atria and
ventricles. Our comprehensive imaging
creates individualized 3-D roadmaps
that interventional cardiologists and
cardiovascular surgeons use for virtual
procedure planning as well as actual
procedural facilitation. The integration
of 3D imaging and mapping systems has
allowed us to reduce the use of fluoroscopy
at various stages of procedures and, in
many instances, eliminate the use of
fluoroscopy altogether. We have implanted
pacemakers without the use of fluoroscopy
in certain unique circumstances.
The CardioVascular Thoracic Institute
has broad expertise and many approaches
to treat patients with atrial fibrillation
(afib). We individualize the treatment and
management plan for each patient with
afib using a variety of approaches. Our
physicians also have expertise in treating
adult patients with congenital heart disease
(ACHD) who develop afib, a subgroup of
patients with afib who don’t have many
experienced medical centers at which to
obtain treatment.
We treat patients with complex atrial
fibrillation, including patients with
advanced heart failure or cardiomyopathy.
The range of therapies for patients with
afib includes conservative management
with antiarrhythmic and antithrombotic
pharmacotherapy. Through collaborations
across multiple specialties at Keck
Medicine of USC, we address the
prevention and management of comorbid
conditions. Keck Medicine of USC is
developing a center of excellence focusing
on arrhythmias and breathing disorders
(particularly obstructive sleep apnea and
chronic obstructive pulmonary disease).1,2
We offer state-of-the-art clinical care
focused on a common cluster of diseases
that are interconnected, using a multi-
Figure 1 - An electroanatomic map. The image was created
using a 3D electroanatomic mapping system and depicts a
geometric shell of the left atrium, the mitral valve annulus
(“MA”), the left atrial appendage (“LAA”) and the locations,
sizes and sites of connection of the pulmonary veins to the
left atrium. The left image also demonstrates the locations of
two reference electrophysiologic catheters (yellow and orange
tubes) as well as the locations where ablation lesions were
applied (red dots). All of these can be delineated and followed
in real-time during the mapping and ablation procedures using
the mapping system.
specialty approach that includes physicians
from cardiology, pulmonology, sleep medicine
and otolaryngology.
Catheter ablation has become an increasingly
common procedure to treat patients with
afib, with the goal of eliminating areas that
initiate or maintain afib. Physicians at the
CardioVascular Thoracic Institute perform
150 to 200 afib ablations each year. Catheter
ablation offers superior results at eliminating
afib than current pharmacotherapy.3,4 Some of
the newest developments in catheter ablation
for afib being employed at CVTI are 3-D
electroanatomic mapping systems (see Figure
1) and contact force electrodes.
Two devices have recently been
investigated to close off the left atrial
appendage (LAA), which is believed
to be a source of blood clots in patients
with non-valvular atrial fibrillation. The
Watchman™ device is indicated in patients
who are at risk for thromboembolic
complications and who have a reason to
seek out a non-pharmacologic solution
to manage their afib. The Watchman™
device is deployed by catheter (see Figure
2). Patients receiving the Watchman™
device had fewer hemorrhagic strokes,
cardiovascular/unexplained deaths and
nonprocedural bleeding than patients
receiving warfarin.6,7 Physicians at CVTI
participated in the clinical trials for the
Watchman™ device (PROTECT AF and
PREVAIL).
The Lariat® device is a suture delivery
device that is used by some physicians
to close off the LAA in patients with
afib. Unlike other procedures or devices
that close the LAA, the LARIAT device
does not require anticoagulation after
the procedure, so the Lariat® device can
be used in patients who have an absolute
contraindication to anticoagulation for any
period of time.
Patients with afib who have a need for cardiac
pacing may be candidates for leadless pacemakers
(see Technology Spotlight). Cryoballoon ablation
for pulmonary vein isolation is another option to
treat afib offered at CVTI.5
For patients with atrial fibrillation who are
undergoing a cardiac surgical procedure for
another indication, surgeons at the CVTI
will surgically manage the patient’s afib at the
same time. Several options exist for surgical
management that include an epicardial or
thoracoscopic ablation, ligation of the left
atrial appendage or the Cox-Maze procedure.
The Cox-Maze procedure requires a highly
specialized skill set that CVTI surgeons possess.
Figure 2 - Diagram of the Watchman™ left atrial appendage
closure device implanted. ©2016 Boston Scientific
Corporation or its affiliates. All rights reserved.
USC CardioVascular Thoracic Institute: (323) 442-5849 cvti.KeckMedicine.org
3
USC CardioVascular Thoracic Institute
THE LEADING EDGE
EXPERTISE showcase
Management of Adults with Congenital Heart Disease (ACHD)
The Adult Congenital Heart Disease
(ACHD) program is deeply integrated
with Keck Medicine’s cardiac and
cardiothoracic surgical specialties that
care for pediatric and adult patients,
as well as with other services that offer
specialized and unique services to these
patients including gastroenterology,
hematology, nephrology and
pulmonology. The program director is
board certified in Adult Congenital
Heart Disease Management within the
American Board of Internal Medicine
and works in close collaboration with
The Heart Institute at Children’s
Hospital Los Angeles.
the acquired cardiovascular diseases that
develop in adulthood. The transition
program ensures that this specialized
care is in place when patients reach their
adult years. In addition, patients and
their families are educated and informed
about the importance of follow-up with
a CHD specialist throughout adulthood
and thoroughly prepared to move from
pediatric to adult cardiac care.
At CVTI, we offer a broad spectrum
of therapies to treat patients with
CHD. Percutaneous therapies include
The ACHD program offers novel
and progressive ways to treat
congenital heart disease (CHD)
and associated adult-acquired
cardiac conditions. Two cardiac
surgeons at the CardioVascular
Thoracic Institute have specialty
training for surgical interventions
to treat patients with CHD.
Patients with CHD are a growing
population of patients that require
and benefit from implantable devices.
However, abnormal cardiac anatomy, past
surgical procedures, residual defects and
unconventional or absent vasculature may
complicate or preclude standard device
implantation. Novel device technology and
alternative device implantation techniques
can circumvent these limitations, enabling
us to provide implantable device benefits to
our patients.
We offer and implant the full spectrum
of implantable cardiac devices in
our ACHD patients. This includes
devices such as the subcutaneous
ICD, leadless pacemaker and cardiac
resynchronization therapy devices. We
also offer hybrid surgical/percutaneous
implants that can combine intraand extra-cardiac device hardware.
In addition to comprehensive
implantable device options, we also
offer extraction services and expertise
in treating patients who require
removal of leads from the vasculature
either due to lead malfunction,
damage or infection.
A highlight of the ACHD
program at CVTI is the pediatric/
adult transition program. The
Many patients with a single ventricle
ACHD program director meets
are now surviving into middle-aged
with young adult patients (18
adult life and new cardiac conditions
to 21 years old) with CHD
Figure 3 - An x-ray shows a hybrid device with cardiac resynchronization
are developing in this population that
and their families in a monthly
and defibrillation capabilities being implanted into an adult congenital
previously were not seen because of
transition clinic at Children’s
heart patient. This device contains epicardial and transvenous leads.
a reduced life expectancy. The CVTI
Hospital Los Angeles. The director
is leveraging its expertise with complex
reviews all of the patient’s medical
device closure of atrial septal defects,
cardiac ablation procedures to treat patients
records before an extensive clinic visit
patent foramen ovale, ventricular septal
with a single ventricle who are developing
to discuss conditions, procedures,
defects and patent ductus arteriosus. We
arrhythmias. Our physicians also recognize
future outlook and possible issues that
also offer transcatheter percutaneous
that hepatic complications are a growing
require surveillance and follow-up. This
pulmonary valve replacement and complex
concern in patients with a single ventricle.
transition program helps ensure that
electrophysiology procedures including RF
We are exploring ways to detect this
patients obtain suitable health insurance
catheter ablation and implantable device
complication earlier and collaborating with
as well.
therapies. Our goal is to keep radiation to
our gastroenterology experts to care for
Patients with CHD require life-long
a minimum and we offer reduced-radiation
those who develop hepatic disease.
individualized care with physicians who
fluoroscopy and radiation-free procedures
specialize in CHD and can recognize
when possible.
4
USC CardioVascular Thoracic Institute: (323) 442-5849 cvti.KeckMedicine.org
technology spotlight
New Options for Implantable Cardiac Pacing and Defibrillation
The CardioVascular Thoracic Institute
can tailor pacing and defibrillation
therapy to the needs of the patient,
including devices that can pace or
monitor in one to three cardiac
chambers. With the current and nextgeneration pacing and defibrillation
devices, CVTI is changing the approach
to device implantation and is expanding
the population of patients who can be
effectively managed with these devices.
Our physicians and surgeons are using
their experience across a broad range
of cardiac conditions to apply new
pacemakers and defibrillators for unique
or unusual circumstances (see Case
Study).
Recent developments in pacing and
defibrillation have brought about
new, all-in-one devices: leadless
pacemakers and a subcutaneous
implantable cardioverter-defibrillator
(ICD). Leadless pacemakers are
single chamber pacemakers that
don’t contain wire leads as used in
conventional pacemakers, which are
prone to breakdown and more difficult
to extract than the pacing device itself.8
These devices are indicated for patients
with limited vascular access (possibly
due to a history of multiple cardiac
interventions), dialysis requirement for
renal failure or a high risk of infection.
A leadless pacemaker also has different
implications for the patient’s level of
physical activity and aesthetic needs
than a traditional pacemaker.
The leadless pacemaker is placed
directly into the right ventricular apex
by catheter deployment (see Figure 4).
Results of clinical studies show pacing
capture thresholds and R-wave sensing
amplitudes that were within a suitable
range.9,10 Two leadless pacemakers,
the Nanostim™ device and the Micra™
device, are approved for use in the
European Union. The CVTI participated
in clinical trials for the Nanostim™ device
(St. Jude Medical) and can offer this device
to patients through continued access.
The subcutaneous ICD (or S-ICD™) is an
FDA-approved implantable cardioverterdefibrillator that is implanted under
the left breast and the lead is placed
subcutaneously left of the sternum.11
Fluoroscopy is not necessary to place
the S-ICD™. The S-ICD™ is indicated
for patients with limited vascular access
(similar to leadless pacemakers), a
mechanical barrier to placing a right
ventricular defibrillator lead, a risk for
valvular disease, congenital heart disease or
active patients who may be prone to lead
breakdown. The S-ICD™ does not provide
pacemaker or cardiac resynchronization
therapy capabilities as some traditional
ICDs do. Results of clinical studies
show that 90% of VT/VF events were
terminated with the first shock and 98%
were terminated within the 5 shocks
available.12
CVTI is committed to providing patients
leading edge procedures and devices to
treat their cardiac electrophysiological
conditions as appropriate.
Figure 4 - A fluoroscopy image of a
leadless pacemaker being placed into the
right ventricular apex. The pacemaker is
introduced by a catheter and is anchored
to the endocardium with a helical fixation
point.
5
USC CardioVascular Thoracic Institute
THE LEADING EDGE
Clinical Trials
Continued from page 1
used to characterize cardiovascular
disease processes including clinical
history, cardiovascular risk factors,
electrocardiographic, electrophysiologic
and anatomic/physiologic findings of
other cardiovascular diagnostic studies
in patients with electrophysiologic or
structural heart disease.
location for left ventricular pacing leads in
patients with non-left bundle branch block
heart failure who are receiving cardiac
resynchronization therapy (NCT01983293).
The NAVIGATE X4 study is evaluating
two new pacing and defibrillation leads
(NCT02071173).
Physicians at CVTI are still involved
The STAR-VT trial is examining the role
in continued access to the Nanostim
of the FlexAbility™ ablation catheter
leadless pacemaker that was evaluated
system as it compares to routine drug
in the LEADLESS II pacemaker study
therapy to reduce ventricular tachycardia
(NCT02030418). EFFORTLESS is a post(NCT02130765). An NIH-sponsored clinical market registry examining the clinical
trial is evaluating the outcomes of catheter effectiveness of the subcutaneous ICD
ablation for persistent afib when an ethanol system in patients with ventricular
infusion through the vein of Marshall
tachyarrhythmias (NCT01085435). Quad
is added to the standard pulmonary
PAS is a post-market study examining
vein antral isolation (PVAI) procedure
the acute and chronic performance of a
(NCT01898221).
quadrupolar CRT-D device (NCT01555619).
Multiple studies are underway in the fields An investigator-initiated, retrospective
of pacing and defibrillation. The ENHANCE clinical trial is examining the minimum
CRT study is examining the effect of implant energy required for successful defibrillation
of induced ventricular fibrillation in patients
with chronic kidney disease (stage III or
higher) or end-stage renal disease. The
study will also examine modifications that
can effectively lower the defibrillation
threshold in these patients.
The Center For Body Computing used
a smartphone-enabled ECG device
(AliveCor) to monitor heart rhythms in the
general adult public. CBC enrolled over
1750 participants. At an interim analysis of
half of the population in May 2015, atrial
fibrillation was detected in 93 unique
subjects (from the 865).
For more information on any of the clinical
trials or to inquire about enrolling a patient,
please contact
Melissa Minor, RN
(323) 442-7983 or:
[email protected]
USC Electrophysiology
Program Team
Rahul Doshi, MD
USC Interventional
Program Team
Leonardo C. Clavijo, MD, PhD
Associate Professor of Clinical Medicine
Director, Vascular Medicine and Peripheral Interventions
Associate Professor of Medicine
Director, Electrophysiology Program
Ray V. Matthews, MD
Philip Chang, MD
Professor of Clinical Medicine
Chief, Cardiovascular Medicine
Assistant Professor of Clinical Medicine
Medical Director, Adult Congenital Heart Disease
Care Program
Tomas Konecny, MD
Assistant Professor of Clinical Medicine
Leslie Saxon, MD (Clinical Scholar)
Professor of Clinical Medicine
Executive Director, USC Center for Body Computing
Jerold S. Shinbane, MD
Professor of Clinical Medicine
Director, USC Arrhythmia Center
Director, Cardiovascular Computed Tomography
Mary Huntsinger, ACNP
EP Nurse Practioner
Brenda Beltran
Project Specialist
Case study
A 35-year-old male was referred to the CardioVascular Thoracic
Institute with a challenging combination of congenital complete
heart block and Hansen’s disease (leprosy). While the heart
block required permanent pacemaker support, the patient
experienced significant morbidity related to recurrent breakdown
and infection of the pacemaker pocket site secondary to the
extreme skin fragility that resulted from Hansen’s disease. These
infectious complications required the complete removal of
pacemaker generators, transvenous leads and epicardial pacing
systems. These components were subsequently reimplanted
at alternate sites, but suffered the same complications (see
Figure 5). The complications dramatically affected the patient’s
life, resulting in his inability to maintain consistent work, a
tremendous financial burden and a substantial impact on his
family life because of frequent hospitalizations and procedures.
After his last epicardial pacemaker was compromised, our team
explored the option of implanting a leadless pacemaker, which
theoretically had the advantage of providing permanent pacing
support without the involvement of any materials implanted
under the skin or within the vasculature. Given that the device
is investigational and that the indication for implantation in this
6
patient’s case differed from
the conventional criteria,
CVTI physicians obtained
approval for compassionate
use of the leadless pacemaker
from the US Food and Drug
Administration and the device
manufacturer. The leadless
pacemaker was implanted into
the patient’s right ventricle
without complication.
Excellent device function
Figure 5 - Photo of the patient’s torso
was noted at the time of
showing multiple skin sites compromised by
implant as well as throughout breakdown and infection following placement
of pacemakers in two separate procedures.
subsequent follow-up, now
The pacemakers were indicated to treat the
patient’s congenital complete heart block. The
extending to 18 months.
patient also had Hansen’s disease, which led to
Since the leadless device was the infectious complications.
implanted, he has had no
hospitalizations or urgent care visits for pacemaker infections as
he repeatedly had in the past. The patient has returned to work
full-time and is enjoying a full life.
References
1. Konecny T, Park JY, Somers KR, Konecny D, Orban M. Relation of chronic
obstructive pulmonary disease to atrial and ventricular arrhythmias. Am J
Cardiol. 2014;114(2):272-277.
2. Konecny T, Geske JB, Ludka O, Orban M, Brady PA, Aubudiab MM. Decreased
exercise capacity and sleep-disordered breathing in patients with
hypertrophic cardiomyopathy. Chest. 2015;147(6):1574-1581.
3. Pappone C, Rosanio S, Augello G, et al. Mortality, morbidity, and quality of life
after circumferential pulmonary vein ablation for atrial fibrillation. J Am Coll
Cardiol. 2003;42(2):185-197.
4. Calkins H, Reynolds MR, Spector P, et al. Treatment of atrial fibrillation with
antiarrhythmic drugs or radiofrequency ablation: wo systematic literature
reviews and meta-analyses. Circ Arrhythm Electrophysiol. 2009;2(4):349-361.
5. Packer DL, Kowal RC, Wheelan KR, et al. Cryoballoon ablation of pulmonary
veins for paroxysmal atrial fibrillation: first results of the North American
Arctic Front (STOP AF) pivotal trial. J Am Coll Cardiol. 2013;61(16):1713-1723.
6. Holmes DR, Kar S, Price MJ, et al. Prospective randomized evaluation of
the Watchman left atrial appendage closure device in patients with atrial
fibrillation verus long-term warfarin therapy. J Am Coll Cardiol. 2014;64(1):112.
8. Reddy VY, Exner DV, Cantillon DJ, et al. Percutaneous implantation of an
entirely intracardiac leadless pacemaker. N Engl J Med. 2015;373(12):1125-1135.
9. Reddy VY, Knops RE, Sperzel J, et al. Permanent leadless cardiac pacing:
results of the LEADLESS trial. Circulation. 2014;129(14):1466-1471.
10.Ritter P, Duray GZ, Steinwender C, Soejima K, Omar R. Early performance of
a minaturized leadless cardiac pacemaker: the Micra transcatheter pacing
study. Eur Heart J. 2015;36(37):2510-2519.
11.Chang PM, Doshi R, Saxon LA. Subcutaneous implantable cardioverterdefibrillator. Circulation. 2014;129(23):e644-646.
12.Burke MC, Gold MR, Knight BP, Barr CS, Theuns DAMJ, Boersma LVA. Safety
and efficacy of the totally subcutaneous implantable defibrillator: 2-year
results from a pooled analysis of the IDE study and EFFORTLESS registry. J Am
Coll Cardiol. 2015;65(16):1605-1615.
13.Daubert J-C, Saxon L, Adamson PB, et al. 2012 EHRA/HRS expert consensus
statement on cardiac resynchronization therapy in heart failure: implant
and follow-up recommendations and management. Heart Rhythm.
2012;9(9):1524-1576.
7. Reddy VY, Sievert H, Halperin J, et al. Percutaneous left atrial appendage
closure vs warfarin for atrial fibrillation: a randomized clinical trial. JAMA.
2014;312(19):1988-1998.
USC CardioVascular Thoracic Institute: (323) 442-5849 cvti.KeckMedicine.org
7