grupo latido

ANSWERS
Dear Potro What a beautiful strip! We taught our fellows on the basis of differential diagnosis: In this
case: Wide Complex Beats (or "fat" beats):
1. Ventricular Origen: a. Premature ventricular contractions (PVCs) b. Automatic ectopic beats
(Parasystole)
2. Supraventricular Origen: a. Aberrant Conduction: HR dependent b. Preexcited beats c. Intermittent
conduction delay (LBBB, etc)
Your case:
I see three (3) populations of beats (see lead I):
1. First population represented by beats 1,2,5,6 (the widest) 2. Second population represented by beats
3,7 3. Third population represented by beat 4. In fact this beats has the appearence of a "son" between
the first and the second population.
This beat is a FUSION beat. Before this beat, there is a non- conducted P-wave.
4. The interval between beats 1 & 2 and between beats 5 & 6 is identical.
Diagnosis: Ventricular Parasystole.
Ventricular parasystole is an automatic rhythm originated in any part of the ventricles, that compete with
the underlying rhythm of the patient.
In its typical form is characterized by 3 signs:
1. Variable coupling interval (not well seen in this trace becasue is TOO short). the original papers of
Castellanos A (see mid 70s) he requiered at least 2 minutes of continuos recordings to call a rhythm a
parasystole.
The variable coupling interval is giving by the automatic nature of this arrhythmia.
2. Fusion beats: this is the consequence of 2 activation fronts depolarizing the ventricle simultaneously
(the sinus beat + the automatic focus) 3. Minimum multiple law: this referes to the minimum cycle length
of discharge of the parasystolic focus. Sometimes is very difficult to find it due to the influence of
autonomic tone over the ectopic focus as well as a modulation induced by the uderlying rhythm
(entry/exit block). If you have the 3 components, the arrhythmia is called TYPICAL parasystole (only seen
in 10% of the cases) but if you see variable coupling interval and fusion ONLY is called ATYPICAL or
MODULATED parasystole (90% of the cases). Of course, you can prove me wrong, as the strip is a bit
short to be conclusive.
But I enjoyed the intelectual exercise, thanks Potro!
Adrian Baranchuk
Spanish
Estimado Potro: ¡Qué hermoso trazado! Les enseñamos a nuestros colegas sobre la base del
diagnóstico diferencial: En este caso: latidos complejos anchos (o latidos “gordos”):
1. Origen ventricular: a. Extrasístoles ventriculares b. Latidos ectópicos automáticos (parasístole)
2. Origen supraventricular a. Conducción aberrante: dependiente de FC b. Latidos pre-excitados c.
Retardo de conducción intermitente (BRI, etc.)
Su caso:
Veo tres (3) poblaciones de latidos (ver derivación I):
1. Primera población representada por latidos 1,2,5,6 (los más anchos) 2. Segunda población
representada por latidos 3,7 3. Tercera población representada por el latido 4. De hecho, estos latidos
tienen la apariencia de un “hijo” entre la primera y segunda población. Este latido es un latido de
FUSIÓN. Antes del mismo, hay una onda P no conducida.
4. El intervalo entre los latidos 1 y 2 y entre los latidos 5 y 6 es idéntico.
Diagnóstico: parasístole ventricular.
La parasístole ventricular es un ritmo autonómico que se origina en cualquier parte de los ventrículos,
que compite con el ritmo subyacente del paciente.
En su forma típica se caracteriza por 3 signos:
1. Intervalo de acoplamiento variable (no se ve bien en este trazado porque es MUY corto). Los trabajos
originales de Castellanos A (ver mediados de los 70) requerían al menos 2 minutos de registro continuo
para llamar a un ritmo parasístole.
El intervalo de acoplamiento variable es dado por la naturaleza automática de esta arritmia.
2. Latidos de fusión: son la consecuencia de dos frentes de activación que despolarizan el ventrículo
simultáneamente (latido sinusal+foco automático).
3. Ley de múltiples mínimos: esto se refiere a la longitud mínima de ciclo de descarga del foco
parasistólico. A veces es muy difícil hallarlo por la influencia del tono autonómico sobre el foco
ectópico así como una modulación inducida por el ritmo subyacente (bloqueo de entrada/salida). Si se
tienen 3 componentes, la arritmia es llamada parasístole TÍPICA (observada solamente en el 10% de los
casos) pero si se observa un intervalo variable de acoplamiento y fusión SOLAMENTE, se llama
parasístole ATÍPICA o MODULADA (90% de los casos). Por supuesto, Ud. puede decir que estoy
equivocado, puesto que el trazado es un poco corto para ser concluyente.
Pero disfruté el ejercicio intelectual, ¡gracias Potro!
Adrian Baranchuk
Beats with wide QRS are seen (image of CLBBB, superior axis), which compete with
an apparently baseline rhythm with narrow QRS, not sinus, at times reaching fusion
beats.
It seems to be a pacemaker in the VVI mode at 100 bpm, on rhythm of AF with
moderate ventricular response. The accuracy in the LC of the "wide"
rhythm and
a possible spike in the 2nd beat in V3, make me lean toward this diagnosis.
Best regards for everyone. Excellent tracing.
Damian Longo
Spanish
Se observan latidos con QRS ancho (imágen de BCRI, eje superior), que compiten con
un ritmo aparentemente basal con QRS estrecho, no sinusal, logrando por momentos
latidos de fusión.
Impresiona tratarse de un marcapasos en modo VVI a 100 lpm, sobre ritmo de FA de
moderada rta ventricular. La exactitud en la LC del ritmo "ancho"
y uma posible espiga en el 2do latido en V3 hacen inclinarme hacia ese Dx.
Saludos cordiales a todos. Excelente trazado.
TPC Damian Longo
Potro,
Remarkable electrophysiologists, I work on morphological electrocardiology, but I will
try from my point of view, to analyze this tracing.
The CLBBB-like beats have the first vector with very slow depolarization, similar to the
first vector of a WPW beat. This vector evolves into a fibrotic area. The frontal vectorial
orientation is shifted to the left, indicating that its origin is the posterior paraseptal area
of the right ventricle.
This arrhythmia makes me suspect an ischemic process (where often, it is the only hint
of ischemic process, of a silent area for the ECG).
Atypical LA morphology of V5, V6, explained by the extreme shift to the left of PVC.
The third beat seems to be it is a capture of retrograde P with first degree block. This
beat is related to the second beat, since it appears at the same distance in the last beat
of the record in regard to the penultimate (arrhythmia in mirror, where the beats are
repeating in the same sequence).
Of course, we need a longer recording, but there’s no doubt that the
4 beats
are related to each other. The fourth beat is a fusion beat, in favor of sinus beat, since
the PR segment allows for a greater anterograde depolarization.
TO CONCLUDE, VENTRICULAR ARRHYTHMIA ORIGINATED IN THE RIGHT
PARASEPTAL AREA WITH MIRROR BEATS.
I hope this analysis of an old electrocardiographist may give you a clue on this
interesting case.
Samuel Sclarovsky
Emeritus professor university Tel Aviv Israel
Spanish
Potro
Destacados electrophisiologista , yo me dedico a la electrocardiologia morfologica,
pero intentare de mi punto de vista de analizar este trazado Los latidos CLBBB like
tienen el primer vector con depolarizacion muy lenta , similar al primer vector de un
latido WPW.Este vector evoluciona en una zona fibrotica . La orientacion vectorial
frontal esta desviado hacia la izquierda, indicando que su origen es la zona paraseptal
posterior del ventriculo derecho Esta arritmia hace sospechar de un proceso isquemico
(donde muchas veces es el unico indicio de un proceso iequemico, de una zona muda
al electro) . LA morfologia atipica de v5,v6 ,se explica por la desviacion extrema hacia
la izquierda de la sPVC'S El tercer latido me parece que es una captura de una P
retograda con bloqueo de primer grado. Este latido esta relacionado con el segundo
latido, ya que aparece en la misma distancia en el ultimo latido del registro con
respecto al anteultimo (arritmia en espejo, donde los latidos se van repitiendo en la
misma sequencia) Por supuesto necesitamos un registro mas largo . pero no hay duda
que los 4 latidos estan relacionado entre si. El cuarto latido es un latido fusionado, en
favor de latido sinusal ya que el segmento P-R permite una mayor depolarizacion
anterograda EN CONCLUSION ARRITMA VENTRICULAR ORIGINADA EN LA ZONA
PARASEPTAL DERECHA, CON LATIDOS EN ESPEJO Espero que este analisis de un
viejo electrocardiografista les pueda dar la clave sobre este interesante caso
Samuel Sclarovsky
Emeritus professor university Tel Aviv Israel
My dear Adrian, is just a modest apprentice of electrocardiography, with too much
modesty to express his ideas before so many experts.
However, and between the proposed diagnoses – accelerated idioventricular rhythm,
which I read requires at least three premature ventricular contractions in a row, and
parasystole – I lean toward the latter, and to be on your good side.
Looking at the Chapter on Ventricualr Arrhythmias from the book “ECG Interpretation”
by Zainul Abedin and Robert Conner, the diagnostic criteria mentioned for parasystole
are: "1) variable coupling intervals, 2) interectopic intervals that are constant or have a
common denominator, and 3) fusion beats. A coupling interval is the interval between a
sinus beat and the following ectopic beat. An interectopic interval is the interval
between consecutive ectopic beats, including any intervening sinus beats".
Warm regards and thank you for making me read and learn.
Spanish
Mi querido Adrián, es un humilde aprendiz de la electrocardiografía, con demasiado
pudor para expresar su parecer delante de tantos expertos. No obstante, y entre los
diagnósticos postulados -RIVA, que leí que requiere al menos tres extrasístoles
ventriculares seguidas, y Parasístole- me inclino por lo segundo y no por quedar bien
contigo. Mirando el capítulo de Ventricular Arrhytmias del libro ECG Interpretation de
Zainul Abedin y Robert Conner, se menciona que los criterios de Dx de parasístole son:
"1) intervalos variables de acoplamiento, 2) intervalos interectópicos que son
constantes o tienen un denominador común, y 3) latidos de fusión. Un intervalo de
acoplamiento es el intervalo entre un latido sinusal y el siguiente latido ectópico. Un
intervalo interectópico es el intervalo entre latidos ectópicos consecutivos, incluyendo
cualquier latido sinusal interviniente".
Un abrazo y gracias por obligarme a leer y aprender.
Name: RS; Sex: Female; Age: 70 yo; Ethnic Group: Caucasian; Weight: 76Kg; Height: 1.58 m;
Biotype: Endomorph; Date: 10/02/2009; Time: 11:05AM.
{
HR: 100bpm
3
C
4
F
7
C
Clinical Diagnosis: Diabetes Mellitus and coronary insufficiency. ECG Diagnosis: HR 100bpm. Beats 3 and 7 are ventricular
captures (C) conducted sinus beats. Beat 4 ventricular fusion beat (F). Final Diagnosis: Probably Accelerated Idioventricular
Rhythm (AIVR). Why probably? Because the certain diagnosis of AIRV requires at least three premature ventricular contractions.
Name: RS; Sex: Female; Age: 70 yo; Ethnic Group: Caucasian; Weight: 76Kg; Height: 1.58 m;
Biotype: Endomorph; Date: 10/02/2009; Time: 12:40PM.
C
Now we are certain that it is an AIVR because more than 3 beats in sequence are observed.
Where is the focus? Answer in next slide.
The focus is located in right ventricle,
Why?
Because the basal complexes have Complete Left Bundle Branch Block Pattern-like
(CLBBB) VT with CLBBB morphology and extreme axis shifted to the left, is
indicative of RVIT origin which always suggests underlying structural heart disease.
Ao
Ao
PA
PA
RVOT
RA
RA
RVIT
RV
RV
APEX
Ao
PA
RA
RVIT
First I Strip
Date: 10/02/2009 Time: 11:05AM
HR: 100bpm
C
C: Capture beat, capture complex or ventricular capture complex
Second I Strip
Date: 10/02/2009 Time: 12:40
ACCELERATED
IDIOVENTRICULAR RHYTHM
CAN MOST EASILY BE
DISTINGUISHED FROM VT IN
THAT THE RATE IS LESS
THAN 130 AND USUALLY
LESS THAN 100 bpm.
HR: 94bpm
C
ACCELERATED IDIOVENTRICULAR
RHYTHM OR SLOW VT
MONITOR LEAD
Broadened QRS with “slow” rate (100 bpm).
If the ECG reveal wide QRS tachycardia with a narrow complex beat during a wide
complex tachycardia suggests a capture or fusion beat in the setting of VT.
However, there are situations where SVT can also manifest this way (1).
Patients who are misdiagnosed with VT because of ECG artifact may be subjected
to unnecessary procedures.
Physicians (n = 766) were surveyed with a case simulation that included a two-lead
electrocardiographic monitor tracing of artifact simulating a wide-complex
tachycardia. The rhythm strip was not recognized as artifact by 52 of the 55
internists (94%), 128 of the 221 cardiologists (58%), and 186 of the 490
electrophysiologists (38%). 156 of the 181 electrophysiologists (88%), 67 of the 126
cardiologists (53%), and 14 of the 15 internists (31%) who misdiagnosed the rhythm
as VT recommended an invasive procedure for further evaluation or therapy.
ECG artifact that mimics VT may frequently result in patients being subjected to
unnecessary invasive cardiac procedures. Physicians should include artifact in their
differential diagnosis of wide complex tachycardias to minimize unneeded
procedures.
1.
Rosman J, Tawil J, Hanon S, Schweitzer P. Wide QRS tachycardia: what is the rhythm? Ann Noninvasive
Electrocardiol. 2006 Oct;11:354-356.
ACCELERATED IDIOVENTRICULAR RHYTHM
CONCEPT: It is a ventricular rhythm with a sequence of ≥ 3 consecutives monomorphic
ectopic ventricular beats, lasting less than 30 s gradual onset with a long coupling interval
and the end by a gradual decrease of the ventricular rate or increase of the sinus rate
and, last but not least, by a good prognosis. Its heart rate between 50 bpm and 130 bpm.
The rhythm is accelerated because it usually is > to the sinus one, in this case, it is called
ventricular rhythm with isorhythm. It is not an escape rhythm, it is a competing rhythms
self-limited and it is usually related to myocardial ischemia. In Accelerated Idioventricular
Rhythm (AIVR), the rate of cardiac contraction is determined by the intrinsic rate of
depolarization of the cardiac cells. It can be present at birth. In this last case, the patient
had an excellent prognosis because the tachycardias resolved, and eventually the
patients were in sinus rhythm. It is important to establish the diagnosis when it occurs to
differentiate this benign phenomenon from dangerous paroxysmal ventricular
tachycardia(1).
SYNONYMOUS: Non-paroxysmal VT, slow ventricular tachycardia(2), ventricular rhythm
with isorrhythm, benevolent rhythm(3)
SEMANTIC DISCUSSION: the term tachycardia implies the existence of a rhythm with a
natural rate above what is considered to be normal for sinus rhythm; i.e. greater than 100
bpm for adults; therefore, the majority of the improperly called slow VT, with rates
between 50 and 130 bpm, would be left out of this concept.
1.
2.
3.
Freire G, Dubrow I. Accelerated Idioventricular Rhythm in Newborns: A Worrisome But Benign Entity with or
without Congenital Heart Disease. Pediat Cardiol. 2008; 29: 457-462.
Leitz N, Khawaja Z, Been M. Slow ventricular tachycardia. BMJ. 2008 Jul 3; 337:a424.
Martinez-Lopez JI. ECG of the month. Benevolent rhythm. Escape impulses; escape rhythm. J La State Med Soc.
1993 Jun;145:249-252.
POSSIBLES ETIOLOGIES
•
Acute phase of myocardial infarction (MI): present in 15% of the cases(1).
A) Inferior or inferoposterior wall: in this case they originate in the posterior fascicle
of the left bundle branch.
B) Acute phase of MI of anterior wall: in this case, they originate in the anterior
fascicle of the left bundle branch
•
Chronic phase of infarction
•
Thromboangiitis obliterans (Buerger's disease)(2)
1.
2.
Chiladakis JA, Pashalis A, Patsouras N, et.al. Autonomic patterns preceding and following accelerated
idioventricular rhythm in acute myocardial infarction. Cardiology.2001;96:24-31.
Hsu PC, Lin TH, Su HM, Voon WC, Lai WT, Sheu SH. Frequent accelerated idioventricular rhythm in a young
male of Buerger's disease with acute myocardial infarction. Int J Cardiol. 2008 Jul 4;127(2):e64-6.
POSSIBLES ETIOLOGIES
1)
2)
3)
4)
5)
•
During inhalational induction with halothane(1)
•
Associated to ophthalmic timolol/dorzolamide solution(2)
•
After aconite poisoning(3)
•
Associated with desflurane administration(4)
•
Extreme hyperkalemia (K+ > 10. mmol/l)(5)
•
Digitalis intoxication. See next slide.
Chhabra A, Subramaniam R. Sudden appearance of idioventricular rhythm during inhalational induction with
halothane in a child with congenital cataract. J Postgrad Med. 2008 Oct-Dec; 54: 337-339.
Attanasio A, Baglio S, Quatrana M, et. al. Accelerated idioventricular rhythm associated to ophthalmic
timolol/dorzolamide solution. Int J Cardiol. 2004 Jun;95:343-345.
Fujita Y, Terui K, Fujita M, et al. Five cases of aconite poisoning: toxicokinetics of aconitines. J Anal Toxicol. 2007
Apr; 31:132-137.
Marret E, Pruszkowski O, Deleuze A, et al. Accelerated idioventricular rhythm associated with desflurane
administration. Anesth Analg. 2002 Aug; 95: 319-321.
Kes P, Orlić-Cunović D, Trubelja N. A life-threatening complication of extreme hyperkalemia in a patient on
maintenance hemodialysis. Acta Med Croatica. 1995; 49:147-150.
ACCELERATED IDIOVENTRICULAR RHYTHM
PVC
AF
DII
AIVR
Elderly patient, 82 years old, myocardiosclerotic. Digoxin 0.25 mg/day for quite
some time. Absence of P wave, f waves: atrial fibrillation.
From the third beat to the sixth, wide and regular QRS with rate of 110 bpm: AIVR:
Accelerated IdioVentricular Rhythm.
The eighth beat is a premature ventricular contraction (PVC).
In such case, AIVR indicates digitalis intoxication. The dose of serum digoxin was 3
ng/mL. The levels above 2.5 ng/mL in adults are considered to be toxic.
POSSIBLES ETIOLOGIES
•
•
•
•
•
•
1.
2.
3.
4.
5.
6.
7.
8.
No underlying heart disease
In young patients and in newborns(1)
Hypervagotonia in highly conditioned athletes(2).
During the antenatal period(3)
Coronary artery dissection(4)
Congenital diseases(5)
Primary cardiomyopathies(6)
Post-resuscitation(7)
Hypertensive heart disease(8)
Freire G, Dubrow I. Accelerated idioventricular rhythm in newborns: a worrisome but benign entity with or without
congenital heart disease. Pediatr Cardiol. 2008 Mar; 29:457-462.
Nasir JM, Durning SJ, et al.Symptomatic hypervagotonia in a highly conditioned athlete. Clin J Sport Med. 2007
Jan;17:70-71Tsai MS, Huang CH, Chen HR, et al. Postresuscitation accelerated idioventricular rhythm: a potential
prognostic factor for out-of-hospital cardiac arrest survivors. Intensive Care Med. 2007 Sep;33:1628-1632.
Dulac Y, Brosset P, Acar P, et al. Slow ventricular tachycardia presenting in the antenatal period . Arch Mal Coeur
Vaiss. 2004 May;97: 564-566.
Karabinos I, Papadopoulos A, Koulouris S, et al.Spontaneous coronary artery dissection during a dobutamine
stress echocardiography. Echocardiography. 2006 Mar;23:232-234.
Reynolds JL, Pickoff AS. Accelerated ventricular rhythm in children: a review and report of a case with congenital
heart disease. Pediatr Cardiol. 2001 Jan-Feb;22: 23-28.
Grimm W, Hoffmann J, Menz V, et al. Significance of accelerated idioventricular rhythm in idiopathic dilated
cardiomyopathy. Am J Cardiol.2000 Apr 1;85:899-904.
Tsai MS, Huang CH, Chen HR, et.al. Postresuscitation accelerated idioventricular rhythm: a potential prognostic
factor for out-of-hospital cardiac arrest survivors. Intensive Care Med. 2007 Sep;33:1628-1632.
Sideris DA, Kontoyannis DA, Michalis L, et al. Acute changes in blood pressure as a cause of cardiac arrhythmias.
Eur Heart J.1987 Jan;8:45-52.
SIGNIFICANCE OF AIVR IN AMI SCENARIO
Post-reperfusion during coronary thrombolysis in the restoration of the anterograde
coronary flow, which indicates reperfusion. Present in 90% of the cases in the first
24 hs. The incidence of AIRV is six times greater in the patients with reperfusion
confirmed by 90-minute angiography after chemical thrombolysis.
There is still no consensus about whether the AIRV constitutes a marker for
myocardial reperfusion, since there are papers that show absence of significant
difference between reperfused and non-reperfused patients. The value of the
presence of AIVR as a marker of reperfusion is small, but in combination with other
non-invasive markers (ST-segment resolution), its presence is connected with a high
probability of successful reperfusion. Early ventricular arrhythmias are a serious
complication of MI. However, if they are revealed and treated in time, they apparently
do not represent a negative prognostic factor(1).
1.
Osmancik PP, Stros P, Herman D. In-hospital arrhythmias in patients with acute myocardial infarction - the
relation to the reperfusion strategy and their prognostic impact. Acute Card Care. 2008;10:15-25.
SIGNIFICANCE OF AIVR IN AMI SCENARIO
AIRV is an nonspecific marker for reperfusion of the infarct-related artery in AMI
and thus, predate previous observations of the thrombolytic era. Even though,
AIRV was associated with higher tonic vagal tone and lower sympathetic activity,
the occurrence of AIRV had no prognostic impact on the clinical course and was
not able to discriminate between complete and incomplete reperfusion(1).
1.
Bonnemeier H, Ortak J, Wiegand UK, et al. Accelerated idioventricular rhythm in the post-thrombolytic era:
incidence, prognostic implications, and modulating mechanisms after direct percutaneous coronary
intervention. Ann Noninvasive Electrocardiol. 2005 Apr; 10:179-187.
AIRV ECG CHARACTERIZATION
•
Duration of QRS complex: ≥120 ms
•
Constant and bizarre morphology of QRS complexes (monomorphic)
•
Slow rate: between 50 bpm and 130 bpm (usually between 70 and 85 bpm)
•
Regular or almost regular R-R
•
Event SAQRS different from basic rhythm SÂQRS
•
Onset and end of event, gradual and non paroxysmal. The former, marked by
delayed or telediastolic premature ventricular contraction (initial beat with
prolonged coupling) or with idioventricular escape if the basic rhythm was very
slow; the end occurs by acceleration of sinus rhythm or by slowing of tachycardiac
rhythm
•
Depressed sinoatrial activity, with frequent absence of P wave
•
AV dissociation: 70% of the cases
•
Frequent fusion beats at the onset and the end of the event
•
Capture and fusion beats, much more frequent than in paroxysmal VT
•
Frequent coexistence with extrasystolic VT in its unstable form
AIVR PRESENTATION FORMS
This characterization is very important, because it is one of the criteria to follow a
therapeutic attitude or not.
A) STABLE FORM:
Alternation between sinus and ventricular rhythm. The coupling of the first beat is usually
fixed and delayed, and the rate of the different events is usually similar.
B) UNSTABLE FORM:
1) Variable couplings of the different tachyarrhythmic events.
2) Rate of each arrhythmic event is different.
3) Within each arrhythmic event, rate acceleration and deceleration.
4) Frequent association with tachyarrhythmias of rapid rates, generally from the same
focus.