Download Common Cardiac Scenarios

COMMON CARDIAC SCENARIOS
What do we know and how do we treat?
FRED C. BREWER IV, DVM, DACVIM (CARDIOLOGY)
OVERVIEW
¨ 
¨ 
¨ 
INCIDENTAL MURMURS
CONGESTIVE HEART FAILURE AND THE
COUGHING DOG
SYNCOPE AND ARRHYTHMIAS
WHAT DO WE KNOW?
MURMURS
INCIDENTAL MURMURS
Sources of murmurs
REYNOLD’S NUMBER= V X D X D
PATHOLOGIC:
VISCOSITY
¨  Myxomatous degeneration
¨  Pulmonic stenosis
¨  Sub aortic stenosis
¨  Dysplastic valves
AUSCULTATION CLUES:
¨  Endocarditis
1)  Harsh (plateau) murmurs
¨ 
2) 
3) 
4) 
5) 
6) 
3/6 or greater (anywhere)
Diastolic
Continuous
Right sided murmurs
Left/Right apical
INCIDENTAL MURMURS
Sources of murmurs
FUNCTIONAL VS. INNOCENT (NO echo evidence)
REYNOLD’S NUMBER= V X D X D
¨  Anemia
VISCOSITY
¨  Bradycardia
¨  Hyperthyroidism
¨  Athletic heart
¨  DRVOTO (cats)
AUSCULTATION CLUES:
1)  2/6 systolic or less
¨  Aortic hypoplasia (Boxers)
¨ 
2)  Basilar
3)  Localized, Soft
4)  Changes w/respiration or HR
INCIDENTAL MURMURS
Grading
¨ 
SUBJECTIVE ASSESSMENT
MURMUR GRADES:
1- soft focal; audible in quiet room
2- soft easier to auscult; localized
3- moderate intensity; easily ausculted
in multiple chest regions
4- Loud and radiating
5- Palpable Thrill
6- Stethoscope off chest
INCIDENTAL MURMURS
DIFFERENTIALS-PATHOLOGIC MURMURS
SYSTOLIC MURMURS
Left
Right
Apex
Base
Apex
Base
MMVD
PS(PULMONIC STENOSIS) MTVD
VSD
MVDysplasia SAS(SUBAORTIC STENOSIS) TVDysplasia SAS/PS
IE
VSD
PH(PULMONARY HYPERTENSION)
(VENTRICULAR SEPTAL DEFECT)
(MYXOMATOUS MITRAL VALVE DEGENERATION)
(infective endocarditis)
DCM
INCIDENTAL MURMURS
DIFFERENTIALS-PATHOLOGIC MURMURS
DIASTOLIC MURMURS
Left
Right
Apex
Base
MVStenosis
Apex
Base
AI(AORTIC INSUFFICIENCY) TVStenosis AI(AORTIC INSUFFICIENCY)
PI(PULMONIC INSUFFICIENCY)
PI(PULMONIC INSUFFICIENCY)
IE (INFECTIVE ENDOCARDITIS)
CONTINUOUS MURMURS: THINK PDA!
INCIDENTAL MURMURS:
Scenario 1-PEDIATRIC (CANINE)
MURMUR: FUNCTIONAL
2/6 Left basilar
systolic murmur
intensity increases
after exercise
MURMUR: PATHOLOGIC
3/6 or greater
Diastolic, Continuous
Right/Left Apex
ASYMPTOMATIC
6 WEEKS-6 MO (TOY BREED) (Root Kustritz 2011)
6 WEEKS – 1+ YR (GIANT BREED)
Echocardiogram
Wait and Watch-Functional vs. Trivial Congenital Defect
Thoracic radiographs?Correct diagnosis for congenital defects is on differential list 37-40%
(Lamb et al, JSAP 2001)
INCIDENTAL MURMURS:
Scenario 2-ADULT (CANINE) Small Breed
MURMUR:(PATHOLOGIC)
3/6 left apical systolic
SYMPTOMATIC
ASYMPTOMATIC
TREAT CHF +
THX RADS +
ECHO +
BLOODWORK
THX RADS + ECHO
BLOODWORK
ECHOCARDIOGRAM THORACIC
RADIOGRAPHS
NT-Pro BNP
WATCHFUL
WAITING
INCIDENTAL MURMURS:
Scenario 2-ADULT (CANINE) Small Breed
MURMUR:(PATHOLOGIC)
3/6 left apical systolic
ECHOCARDIOGRAM
ACCURATE (Tse et al JVECC 2013)
DISEASE SEVERITY
CONCURRENT DISEASE
PROGNOSIS
CKCS MMVD VHS:
11 at 3.5-4yr before CHF
11 at 2.5-3yr before CHF
11.25 1.5-2yr before CHF
11.7 0.5-1yr before CHF
13.25 at time of CHF (Lord et al JVIM, 2011)
ASYMPTOMATIC
THORACIC
RADIOGRAPHS
NT-Pro BNP
WATCHFUL
WAITING
MURMUR INTENSITY
AND DISEASE SEVERITY
CARDIOMEGALY=
634pmol/L (284-2007pmol/L) LOUDER=MORE SEVERE
NO CARDIOMEGALY=
(Lungvall et al AJVR 2009)
378pmol/L (175-1101pmol/L)
(Chetboul et al, JVIM 2009)
INCIDENTAL MURMURS:
Scenario 3-ADULT (CANINE) Large Breed
2/6 LEFT APICAL SYSTOLIC MURMUR
FUNCTIONAL VS. PATHOLOGIC OVERLAP
THINK: CHRONIC VALVE DISEASE VS. DILATED CARDIOMYOPATHY
(LESS LIKELY: INFECTIVE ENDOCARDITIS)
AUSCULTATION: UNRELIABLE
THORACIC RADIOGRAPHS: LACKS DETAIL TO ASSESS SEVERITY
NT-Pro BNP-DOBERMAN- >550pmol/L suggest occult DCM (Sen (78.6%),
Sp (90.4%)) (Wess et al AJVR 2011)
ECHOCARDIOGRAM
INCIDENTAL MURMURS:
Scenario 4-GERIATRIC Large/Small Breed
MEDIUM TO LARGE BREED DOGS
SMALL BREED DOGS
LEFT APICAL
SYSTOLIC MURMUR
>20kg
THORACIC RADIOGRAPHS
+
ECHOCARDIOGRAM
<20Kg
THORAX
RADIOGRAPHS
THINK: MMVD VS. DCM (RARELY INFECTIVE ENDOCARDITIS)
ECHO
THINK: MMVD
INCIDENTAL MURMURS:
Scenario 5-PEDIATRIC (FELINE)
UP TO 6 MONTHS OF AGE
(Root Kustritz 2011)
ANEMIA
(LOW HCT AND THIN CHEST WALL)
INDUCIBLE MURMURS
DRVOTO
HYPERTROPHIC CARDIOMYOPATHY
ANTERIOR MOTION
(DLVOTO, SAM( SYSTOLIC
)
OF THE MITRAL VALVE
CONGENITAL DEFECTS (VSD)
DRVOTO
(DYNAMIC RIGHT VENTRICULAR
OUTFLOW TRACT OBSTRUCTION)
(DYNAMIC RIGHT VENTRICULAR
OUTFLOW TRACT OBSTRUCTION)
SOFT, MUSICAL
HIGH FREQUENCY
MID-SYSTOLIC
<2/6
USUALLY SYSTOLIC
>3/6
AUSCULTATION-LIMITED VALUE
THORACIC RADIOGRAPHS-R/O SEVERE DISEASE-ALSO LIMITED
NT-Pro BNP-NO PUBLISHED DATA
ECHOCARDIOGRAM-RECOMMENDED
INCIDENTAL MURMURS:
Scenario 6-ADULT/GERIATRIC (FELINE)
ANEMIA
(LOW HCT AND THIN CHEST WALL)
INDUCIBLE MURMURS
DRVOTO
(DYNAMIC RIGHT VENTRICULAR
OUTFLOW TRACT OBSTRUCTION)
HYPERTHYROIDISM
SYSTEMIC HYPERTENSION
HYPERTROPHIC CARDIOMYOPATHY
ANTERIOR MOTION
(DLVOTO, SAM( SYSTOLIC
)
OF THE MITRAL VALVE
CONGENITAL DEFECTS (VSD)
DRVOTO
(DYNAMIC RIGHT VENTRICULAR
OUTFLOW TRACT OBSTRUCTION)
INCIDENTAL MURMURS:
Scenario 6-ADULT/GERIATRIC (FELINE)
SYSTOLIC MURMURS ARE COMMON:
1)  OVERTLY HEALTHY CATS (16-44%)1
2)  ASYMPTOMATIC, MURMUR, HEART DISEASE (31-77%)2
3)  HCM AND INCIDENTAL MURMURS (18-62%)3
4)  DRVOTO AND INCIDENTAL MURMURS (19-35%)3
5)  MURMURS ARE DYNAMIC4
CATS DO WHAT THEY WANT!
1) 
2) 
3) 
4) 
Cote et al JAVMA 2004, Drourr et al JVIM 2010, Paige et al JAVMA 2009, Wagner et al JVIM 2010
Bonagura 2011,Cote et al JAVMA 2004, Dirven et al JVIM 2010, Paige et al JAVMA 2009, Wagner et al JVIM 2010, Nakamura 2011
Bonagura 2011, Rishniw 2002, Cote et al JAVMA 2004, Allen et al JVIM 2009, Paige et al JAVMA 2009, Wagner et al JVIM 2010, Nakamura et al JVFS 2011
Paige et al JAVMA 2009
INCIDENTAL MURMURS:
Scenario 6-ADULT/GERIATRIC (FELINE)
1) AUSCULTATION-LIMITED VALUE
2) THORACIC RADIOGRAPHS-HELPFUL
A) VHS > 9.3 SUGGEST CARDIAC CAUSE FOR DYSPNEA
(Sleeper et al JAVMA 2013)
B) 28-72% accuracy (Schober et al JVIM 2007)
3) NT-Pro BNP- HAS VALUE
<50pmol/L cardiomyopathy unlikely (Fox et al JVIM 2011)
>100pmol/L suggests structural heart disease
4) ECHOCARDIOGRAM-DIAGNOSTIC TEST
OF CHOICE
INCIDENTAL MURMURS
CLINICAL PEARLS
FUNCTIONAL VS. PATHOLOGIC
WHEN TO PURSUE DIAGNOSTICS:
1) 
2) 
3) 
4) 
CLINICAL SIGNS
ANESTHESIA
BREEDING
CONCERNED OWNER
USE YOUR TOOLS:
1)  SIGNALMENT PROFILING
2)  BLOODWORK
3)  THORACIC RADS
4)  NT-Pro BNP
INCIDENTAL MURMURS AND
ANESTHESIA
HEALTHY PATIENTS:
DOG:
BEGIN <10ML/KG/HR THEN 5ML/KG/HR
CAT:
BEGIN <10ML/KG/HR THEN 3ML/KG/HR
2013 AAHA/AAFP Fluid Therapy Guidelines for Dogs and Cats*
CARDIAC COMPROMISE
PATIENTS:
DOG:
2-5ML/KG/HR, THEN STOP
CAT:
1-2ML/KG/HR, THEN STOP
(ANECTDOTAL)
OVERVIEW
INCIDENTAL MURMURS
¨  CONGESTIVE HEART FAILURE AND THE
COUGHING DOG
¨  SYNCOPE AND ARRHYTHMIAS
¨ 
CONGESTIVE HEART FAILURE
Scenario 1- GERIATRIC DOG
COUGH AND A MURMUR
WHICH ONE IS A CARDIAC COUGH?
CONGESTIVE HEART FAILURE
Scenario 1- GERIATRIC DOG
COUGH AND A MURMUR
COUGH = NOT ALWAYS A SPECIFIC FINDING
CONGESTIVE HEART FAILURE
Scenario 1- GERIATRIC DOG
WHICH ONE IS A CARDIAC COUGH?
PHYSICAL EXAM CLUES
AIRWAY COUGH
No murmur (or soft murmur in small breed)
Sinus arrhythmia (HR<140bpm)
RR<40breaths/min
CHF COUGH
Murmur (soft vs. loud)
Tachypneic (RR>40breaths/min)
Tachycardic (HR>140bpm)
+/- Crackles
Dyspnea
CONGESTIVE HEART FAILURE
Scenario 1- GERIATRIC DOG
WHAT ABOUT RESPIRATORY RATES?
AT HOME
RESP RATES
1) OUTPERFORM LABORATORY (BIOMARKERS)
AND DOPPLER ECHOCARDIOGRAPHIC
VARIABLES (Schober et al, JAVMA 2011)
2) PREDICT CHF WITH HIGH ACCURACY
MMVD: RR >40 BREATHS/MIN (100%SP/100%SEN)
DCM: RR >26 BREATHS/MIN
(Schober et al, JAVMA 2011)
MMVD: RR >41 BREATHS/MIN (96%SP/92%SEN)
DCM: RR >34 BREATHS/MIN (100%SP/100%SEN)
(Schober et al, JVIM 2010)
IN CLINIC
RESP RATES
YES, THERE’S AN APP FOR IT!
CARDALIS
BOEHRINGER INGELHEIM
CALCULATOR
SLEEPING RESPIRATORY RATES
NORMAL HEALTHY DOGS
40
35
114 dogs
Breaths/min
30
25
20
15
10
5
0
average
SD
Max
Min
Rishniw et al, RVS 2011
SLEEPING RESPIRATORY RATES
NORMAL VS SUBCLINCAL HEART DISEASE
Subclinical MMVD and DCM
60
Ohad D et al JAVMA 2013
190 dogs
114 dogs
40
Breaths/min
40
30
30
20
20
10
10
0
0
Average
ž 
Rishniw et al, RVS 2011
50
50
ž 
NORMAL
60
SD
Max
93% of dogs had RRRmean<30
98% of dogs had RRRmean<35
Min
average
SD
Max
Min
RESPIRATORY RATES IN CATS
HEALTHY AND SUBCLINICAL HEART DISEASE
SLEEPING AND RESTING RESPIRATORY RATES < 30 BREATHS/MIN
Respiratory rate (breaths/min)
50
CATS
45
40
35
30
25
20
15
10
5
0
SRR mean EN
SRR mean SHD
RRRmean EN
RRRmean SHD
Ljungvall et al, JFMS 2013
RESPIRATORY RATES (SSR AND RRR)
DOGS AND CATS
CLINICAL PEARLS
SINGLE MOST SENSITIVE AND SPECIFIC DIAGNOSTIC
TEST FOR IDENTIFYING LEFT SIDED CONGESTIVE
HEART FAILURE
SRR AND RRR <30 BREATHS/MIN (I STILL USE 40 BREATHS/MIN)
(TRENDS MAY BE MORE IMPORTANT)
CONGESTIVE HEART FAILURE
Scenario 1- GERIATRIC DOG
COURTESY OF MARC KRAUS (DVM, DACVIM)
COURTESY OF MARC KRAUS (DVM, DACVIM)
CONGESTIVE HEART FAILURE
ACUTE AND CHRONIC THERAPY
O2 -PREVENT HYPOXIA
FUROSEMIDE
PRELOAD DIURETICS
SPIRONOLACTONE
A
C
TORSEMIDE
M
An
CATS=THINK THORACOCENTESIS!
CRI-0.77-1mg/kg/hr
DOG: 2-4MG/KG (4-6mg/kg if needed)
CAT: 1-2MG/KG
(VENODILATORS)
DOG: 1-2MG/KG BID
CAT: 1MG/KG BID
USE REMAINS EMPIRICAL
WHY?à 69% REDUCTION IN RISK OF
CARDIAC RELATED DEATHS (Bernay et al JVIM 2010)
1/10TH THE DAILY FUROSEMIDE DOSE BID
CONGESTIVE HEART FAILURE
ACUTE AND CHRONIC THERAPY
O2 -PREVENT HYPOXIA
PRELOAD
VENODILATORS
AFTERLOAD
ARTERIODILATORS
C
M
An
NITROGLYCERINE PASTE
ISOSORBIDE DINITRATE
MIXED ACE-INHIBITORS-ENALAPRIL/BENAZEPRIL
AMLODIPINE
NITROPRUSSIDE
HYDRALAZINE
CONGESTIVE HEART FAILURE
ACUTE AND CHRONIC THERAPY
O2 -PREVENT HYPOXIA
PRELOAD
“INODILATOR”
AFTERLOAD
CONTRACTILITY PIMOBENDAN
M
PROTECT TRIAL:
An
CATS? YES. AND NO.
CATS TOLERATE SIMILAR CANINE
DOSES. (Gordon et al JAVMA 2012)
(Macgregor et al JVC 2011)
PIMO LASTS LONGER (Hanzlizek et al JVC 2012)
QUEST TRIAL: (Haggstrom et al JVIM 2008)
DIGOXIN
260 DOGS (MMVD+CHF+CONVENTIONAL THERAPY)
DOBUTAMINE
PIMO VS BENAZEPRIL
DOPAMINE
(267 VS. 140 DAYS)
(Summerfield et al JVIM 2012)
76 DOBIES OCCULT DCM
PIMO VS. NO PIMO
(623 VS. 466 DAYS)
CONGESTIVE HEART FAILURE
ACUTE AND CHRONIC THERAPY
O2 -PREVENT HYPOXIA
WHAT ABOUT HCM CATS?
PRELOAD
AFTERLOAD
CONTRACTILITY
HEART RATE
MYOCARDIAL OXYGEN DEMAND CONTRACTILITY
SYSTEMIC VASCULAR
An
RESISTANCE
ATENOLOL HAD NO EFFECT
ON 5YR SURVIVAL IN
SUBCLINICAL HCM CATS (Schober et al JVC 2013)
ATENOLOL
AMLODIPINE
CONGESTIVE HEART FAILURE
ACUTE AND CHRONIC THERAPY
O2 -PREVENT HYPOXIA
ANTI-ANXIETY
PRELOAD
AFTERLOAD
ANTI-ARRHYTHMICS
CONTRACTILITY
ANTI-THROMBOTICS
MYOCARDIAL OXYGEN DEMAND
An
BUTORPHANOL: 0.2-0.25MG/KG IM/IV
MIDAZOLAM: 0.2MG/KG IM/IV
ACEPROMAZINE: 0.005-0.01MG/KG IM/IV
DEXMEDITOMIDINE: (CATS)
3MCG/KG (GRUMPY)
5MCG/KG (FRACTIOUS)
7MCG/KG (EVIL)
18.75MG SID
LIDOCAINE
MEXILETINE
PROCAINAMIDE
SOTALOL
81MG
EVERY 3 DAYS
PLAVIX VS. ASPIRIN
HEPARIN (UF VS LMWH)
WARFARIN
tPA VS STREPTOKINASE
CONGESTIVE HEART FAILURE
ACUTE AND CHRONIC THERAPY
CATS
CLINICAL PEARLS
ACUTE CHF:
DON’T FORGET
SEDATION!
DOGS
FUROSEMIDE (1-2MG/KG) SID-BID
ACE-INHIBITOR SID-BID
+/- ANTI-THROMBOTICS
CARDIAC TRIFECTA:
FUROSEMIDE (2-4MG/KG) BID
(PLAVIX)
ACE-INHIBTOR SID-BID
PIMOBENDAN (0.25-0.3MG/KG BID
OVERVIEW
INCIDENTAL MURMURS
¨  CONGESTIVE HEART FAILURE AND THE
COUGHING DOG
¨  SYNCOPE AND ARRHYTHMIAS
¨ 
SYNCOPE VS. SEIZURES
DOGS AND CATS
1)  TRIGGER-SITUATIONAL SYNCOPE
1) EXTENSOR RIGIDITY
2) ORAL MUCOSA BLANCHING
2) URINATION/DEFECATION
3) TREMORS/TWITCHING
1) POST-ICTAL PERIOD
2) SEEKING WATER/FOOD
AFTER AN EPISODE
CATS!-SEIZURE-LIKE EPISODES WITH INTERMITTENT HIGH GRADE AVB
AND A POST-ICTAL PERIOD (Penning et al JVIM 2009)
SYNCOPE
DOGS AND CATS
NEURALLY MEDIATED
NEUROCARDIOGENIC
SITUATIONAL SYNCOPE
VASOVAGAL
CARDIAC
STRUCTURAL/FUNCTIONAL
DCM/ARVC
PERICARDIAL EFFUSION
PULMONIC STENOSIS
SUBAORTIC STENOSIS
PULMONARY HYPERTENSION
NON CARDIAC
HYPOGLYCEMIA (INSULINOMA)
ADDISONS DISEASE
SEVERE ANEMIA (IMHA)
EXERCISE-INDUCED-(LABS)
ELECTRICAL DISEASE
HIGH GRADE 2ND AVB
3RD AVB
SICK SINUS SYNDROME
VENTRICULAR TACHYCARDIA
SUPRAVENTRICULAR TACHYCARDIA
SYNCOPE
NEURALLY MEDIATED SYNCOPE
SINUS TACHYCARDIA HR=219BPM
SINUS BRADYCARDIA HR=42BPM
SYNCOPE
DOGS
NEURALLY MEDIATED
NEUROCARDIOGENIC
SITUATIONAL SYNCOPE
(VASOVAGAL)
SMALL BREED DOGS W/ MMVD
LOUD LEFT APICAL SYSTOLIC MURMUR
TRIGGER (EXCITEMENT/COUGH/MICTURITION/DOORBELL/DEFECATION)
C FIBERS (MECHANORECEPTORS)
TRIGGER VAGAL RESPONSE
HYPOTENSION
BRADYCARDIA
TREATMENT?
PRELOAD REDUCTION=
FURSOSEMIDE!
ARRYTHMIAS
SUPRAVENTRICULAR
UPRIGHT AND NARROW COMPLEXES
+/- P WAVES
VENTRICULAR
WIDE AND BIZARRE COMPLEXES
+/- P WAVES
ARRHYTHMIAS
ATRIAL FIBRILLATION (SNEAKERS IN A DRYER)
THINK: A-B-C-D!
A=ATRIAL FIBRILLATION
B=BETA BLOCKERS (ATENOLOL)
C=CALCIUM CHANNEL BLOCKERS
D=DIGOXIN
DILTIAZEM XR (3MG/KG BID)
DIGOXIN (0.003-0.005MG/KG BID)
HR<140->80% 24HR PERIOD
(Gelzer et al JVIM 2009)
ARRHYTHMIAS
VENTRICULAR ECTOPY
WHEN TO TREAT: CLINICAL SIGNS, HEMODYNAMIC STATUS, FAST, COMPLEX (POLYMORPHIC) ECTOPY
IDEALLY HOLTER FIRST!
IV OPTIONS: CRI: 50-80MCG/KG/MIN
1)  LIDOCAINE (2MG/KG) DOSE 2-3 TIMES
2)  PROCAINAMIDE (6-8MG/KG) GIVE SLOW!
ORAL OPTIONS: THINK SPAM!
1)  SOTALOL (2MG/KG) Q 12HR
2)  PROCAINAMIDE (8-20MG/KG) Q6-8HR
3)  AMIODARONE (LOAD THEN REDUCE)
4)  MEXILETINE (5-8MG/KG) Q 8HR
ARRHYTHMIAS
VENTRICULAR ECTOPY
TOP REASONS NOT TO TREAT VENTRICULAR ARRHYTHMIAS:
1)  SLOW V-TACH- (ACCELERATED IDIOVENTRICULAR RHYTHM-AIVR)- HR-60-140BPM
POST-OP SPLENECTOMY, SPLENIC DISEASE, GDV, MYOCARDITIS, CARDIOMYOPATHY
ARRHYTHMIAS
VENTRICULAR ECTOPY
TOP REASONS NOT TO TREAT VENTRICULAR ARRHYTHMIAS:
2) VENTRICULAR ESCAPE BEATS: 3RD AV BLOCK AND SICK SINUS SYNDROME
NO LIDOCAINE!
NEEDS PACEMAKER!!
ARRHYTHMIAS
VENTRICULAR ECTOPY
TOP REASONS NOT TO TREAT VENTRICULAR ARRHYTHMIAS:
3) SUPRAVENTRICULAR WITH ABERRANCY
VT VS. SVT WITH LBBB?
90% OF THE TIME ITS VENTRICULAR
IF NO RESPONSE TO LIDOCAINE/PROCAINAMIDE
THINK SUPRAVENTRICULAR WITH BBB!
VT VS. SINUS RHYTHM WITH RBBB?
ARRHYTHMIAS:
SUPRAVENTRICULAR ANDVENTRICULAR ECTOPY
CLINICAL PEARLS
ATRIAL FIBRILLATION
(A-B-C-D)
DILTIAZEM XR (3MG/KG BID)
DIGOXIN (0.003-0.005MG/KG BID)
VENTRICULAR
ARRHYTHMIAS
ORAL OPTIONS: THINK SPAM!
1)  SOTALOL (2MG/KG) Q 12HR
2)  PROCAINAMIDE (8-20MG/KG) Q6-8HR
3)  AMIODARONE (LOAD THEN REDUCE)
4)  MEXILETINE (5-8MG/KG) Q 8HR
FUROSEMIDE!
QUESTIONS?