Henry Ford Hospital Medical Journal

Volume 21 | Number 4 Article 3

12-1973 Electrical Alternans in Cardiac Tamponade Andreas P. Niarchos

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Recommended Citation Niarchos, Andreas P. (1973) "Electrical Alternans in Cardiac Tamponade," Henry Ford Hospital Medical Journal : Vol. 21 : No. 4 , 169-180. Available at: https://scholarlycommons.henryford.com/hfhmedjournal/vol21/iss4/3

This Article is brought to you for free and open access by Henry Ford Health System Scholarly Commons. It has been accepted for inclusion in Henry Ford Hospital Medical Journal by an authorized editor of Henry Ford Health System Scholarly Commons. FHenry Ford FHosp. Med. Journal Vol. 21, No. 4, 1973

Electrical Alternans in Cardiac Tamponade

Andreas P. Niarchos, M.D.,*

tLECTRICAL alternans has been de­ fined as an alternation of the configura­ tion of the electrocardiographic com­ plexes arising from the same pacemaker and independent of periodic extracardiac Of nine patients with pericardial effusion phenomena.' This electrocardiographic due to various causes, four developed cardiac abnormality was initially observed in the tamponade. Electrical alternans was present In laboratory by Herring in 1909,^ and first all four, being total in three, and ventricular in one. From the diagnostic point of view, the reported clinically the year after by alternans corresponded with the clinical diag­ Lewis.^ Other early reports were those of nosis of cardiac tamponade and the radiologi­ Hamburger, Katz and Saphir," and of cal signs of a large pericardial effusion. The Brody and Rossman.^ The literature on pericardial fluid was hemorrhagic in three pa­ the subject up to 1955 has been reviewed tients and transudate (hydropericardium) in the fourth. In two patients alternans was pres­ by McGregor and Baskind.'' ent with heart rates below 100 per minute. Apart from the exact (1:1) type of electrical Any electrocardiographic complex can alternans, three new types are described; a 2:1, exhibit alternation, the P wave rarely,''" 3:1 and a varying type. It is concluded that a) electrical alternans associated with pericardial the QRS complex,* or the T wave effusion is strongly suggestive of impending or alone,'"'^ or all three complexes can al­ established cardiac tamponade, and b) electri­ ternate simultaneously, when the cal alternans is produced when the heart is phenomenon is called total electrical oscillating within the pericardial sac distended by fluid with a frequency equal to one-half alternans.Although ventricular and (exact alternans), one-third (2.-7 alternans) and total electrical alternans are not very one-fourth (3:1 alternans) ofthe heart rate. The common they are of clinical interest be­ etiology and mechanism of electrical alternans cause they occur primarily in association are discussed. with massive pericardial effusion and cardiac tamponade.',2,6,11,14-1' 8

Two theories have been suggested to explain the mechanism of electrical al­ ternans. One attributes the alternation of the electrocardiographic complexes to alternating conduction within the 'Formerly Medical Registrar, Royal Southern myocardium.' The other theory main­ Hospital, Liverpool, England. Presently fellow. tains that the conduction within the Section on Hypertension, Division of myocardium during alternans remains Metabolic Diseases. unchanged, but that a cyclic motion of Address reprint request to author c/o Henry the heart within a distended pericardial Ford Hospital, 2799 West Grand Boulevard, sac accounts for the alternating elec­ Detroit, Ml 48202 trocardiographic pattern.^''""^° This

169 Niarchos

TABLE I. DIAGNOSIS AND OUTCOME IN THE 9 PATIENTS

Case No. Sex/Age Clinical Type of fluid Electrical Primary Outcome diagnosis and means of alternans Disease confirmation

1 M 5? Tamponade Hemorrhagic Total Acute Survived pericardio­ myocardial centesis infarction

2 M 55 Tamponade Hemorrhagic Total Carcinoma Died pericardio­ L. bronchus centesis and invading necropsy pericardium

3 F 62 Tamponade Hemorrhagic Total Secondary Died pericardio­ carcinomatous centesis and pericarditis, necropsy primary unknown

4 36 Large effusion Hydropericardium Ventricular Malabsorption Survived Albumin/globulin due to celiac ratio = 0.6/1 disease (See text)

5 M 53 Effusion Not known Absent Benign Survived pericarditis

6 M 72 Effusion Hemorrhagic Absent Acute Died Necropsy myocardial infarction

7 M 63 Effusion Hemorrhagic Absent Acute Died Necropsy myocardial infarction

8 M 37 Effusion Not known Absent Uremia Survived

9 M 62 Effusion Hydropericardium Absent Extensive Survived Low albumin/ burns globulin ratio

paper reports the findings of a clinical, diagnosis of celiac disease was confirmed radiological and electrocardiographic by jejunal biopsy. All but two patients study in patients with pericardial effusion were treated in an intensive therapy unit, and tamponade associated with total and under continuous electrocardiographic ventricular electrical alternans, in whom monitoring. All patients had serial elec­ the confirmation of the mechanical trocardiograms and chest radiographs. theory ofthe genesis of alternans is based The cardiothoracic ratio and cardiac on electrocardiographic data. silhouette volume were estimated from data obtained from radiographs (taken Patients and Methods from a distance of six feet with the patient Nine patients were studied, eight standing), as described by Glover, Bax­ males and one female; their age ranged ley, and Dodge.^' In addition the diag­ from 36 to 72 years. Pericardial effusion nosis of large pericardial effusion was with tamponade was diagnosed in four, confirmed by radioisotope heart scans in and pericardial effusion without tam­ two patients (Figure 1), serial phonocar- ponade in five (Table I). The various diag­ diograms (Figure 2), and cardiac noses were established clinically and by catheterization in one (case 4), and by the appropriate laboratory tests. The pericardiocentesis in three patients

170 Electrical Alternans in Cardiac Tamponade

Figure 1, Case 2 Radioisotope heart scan showing large pericardial effusion mainly anterioHy.

(Table I). Necropsy was performed in TABLE II. MAIN CLINICAL FINDINGS four of the cases. The incidence of clin­ IN THE 9 PATIENTS ical, electrocardiographic and radiologi­ cal findings was compared between the Number of patients tamponade and simple effusion groups. Findings Tamponade Effusion The radiological findings were statisti­ Pulsus paradoxus 2 Nil cally analysed using the Student's t test. Sinus arrhythmia 4 4 Two patients from this series (cases 6 and Sinus tachycardia 2 4 7) have been briefly described (heart rate > 100/min.) Raised JVP 4 4 previously." Hypotension 4 1 (systolic BP < 100 mmHg) Results Dyspnea 4 1 Absent heart sounds 2 Nil Clinical Findings Faint heart sounds 2 1 The main clinical findings in both Pericardial friction rub 1 3 Absent apex beat 4 groups are listed in Table II. Pericar- —

171 Niarchos

Figure 2, Case 4 Phonocardiogram; a third heart sound is present. diocentesis relieved the symptoms in although showing initial improvement, cases 1,2 and 3. Furosemide was given to died later from recurrent cardiac tam­ the patient in Case 1 after the pericar­ ponade. The patient with celiac disease diocentesis and his condition improved was treated from the start with gradually. The second and third patients, Furosemide with considerable improve-

TABLE III. RESULTS OF CARDIAC CATHETERIZATION IN CASE 4

Position of catheter tip Pressure (mmHg)

Left ventricle 95/10, early diastole:8, at "a" wave=20 Left atrium a=20, 0=21, x=10, V = 15, y=8, mean=9 Left pulmonary artery wedge a=20, x=9, V=14, y=10, mean = 13 Pulmonary artery 32/16, mean=27 Right ventricle 32/5, early diastole=5, at "a" wave=18 Right atrium a=15, x=10, V=16, y=10, mean=13

Blood oxygen saturation: Normal

172 Electrical Alternans in Cardiac Tamponade

ment. Cardiac catheterization one week later showed cardiac restriction with ele­ vated end-diastolic pressures in all car­ diac chambers (Table HI). He was given a gluten-free diet and the pericardial effu­ HEART sion was reduced when his plasma pro­ teins returned to normal.

Rir-hi Electrocardiographic Findings Lead Sinus arrhythmia and low voltage were V, present in all patients with cardiac tam­ ponade, and in most patients with pericardial effusion. Electrical alternans, however, was present only in the four patients with tamponade. The alternans was total (P-QRS-T) in the first three cases (Figures 3, 4 and 5), and ventricular (QRS) in the fourth. In the first case it was only seen in leads II, and AVF. In the second it was present in all leads, while in the third and fourth case it was better seen in lead Vi. The alternans was not constant in the fourth case. The alternating com­ plexes varied in height from complex to complex even in the same lead (Figure 3), the difference being greater in the right (Vi,V2) and left (V^) chest leads. The elec­ trical alternans disappeared in cases 1, 2 and 3 after aspiration of 30, 65 and 670

V4 mis of pericardial fluid respectively (Fig­ ures 4 and 5), and after treatment with Furosemide in the fourth patient, but the tachycardia persisted in case 3 (Figure 4). The pericardial fluid was hemorrhagic in all, and malignant cells were identified in the fluid removed from the case 3 patient. During reaccumulation ofthe pericardial effusion in cases 2 and 3, several types of 3«5 5.0 3.5 alternans were seen (Table IV). Loft Middle Ri^'-ht The heart and alternans rate and the various electrocardiographic types of al­ ternans before pericardial aspiration are shown in Table IV. A heart rate above 100 per minute was present in two patients 7 n on three occasions, while in the rest of Figure 3, Case 2 the electrocardiograms the heart rate was Total electrical alternans (best seen in lead Ve) below 100 per min ute; total alternans was before pericardiocentesis; the alternans is 1:1 (exact alternans); the numbers represent the present with both fast and slow heart largest part of the QRS in mm, positive or rates. The ratio between heart rate and negative, see text for details.

173 Niarchos

Heart rate

Alternans rate

J, _ .J

Figure 4, Case 3 Heart rate and alternans rate ratio is nearly 3:1 and 4:1, but the type of total alternans is2:1 and 3:1 respectively; the heart rate Is 115 per minute; after pericardiocentesis of 670 mis of fluid the heart rate remains the same, but the alternans has disappeared.

TJr. 30

Figure 5, Case 2, lead V2 Total electrical alternans, 1:1 (exact alternans); heart and alternans rate is nearly 2:1, sinus arrhyth­ mia is present; after pericardiocentesis of 65 mis of fluid the alternans has disappeared.

alternans rate varied; it was always 2:1 was present (Figures 4and 6; Table IV). In when exact (1:1) electrical alternans was addition, a varying type of alternans was present (Figures 3 and 5), but 3:1 and 4:1 seen in case 2 soon before that patient's when a 2:1 and 3:1 respectively alternans death. No constant relationship could be

174 Electrical Alternans in Cardiac Tamponade

T

3

Figure 6, Case 2 Recurrence of cardiac tamponade; lead 1, a 3:1 electrical alternans is present, lead V5,a2:1 alternans is present. TABLE IV. HEART AND ALTERNANS RATE BEFORE AND AFTER PERICARDIOCEN­ TESIS; THE VARIOUS TYPES OF ELECTRICAL ALTERNANS ARE SHOWN

Before pericardiocentesis After ECG Types of electrical alternans Case Heart Alternans Ratio Approximate Ratio (Normal/alter­ Alternating Heart No. rate* (HR) rate (AR) HR/AR ratio HR/AR nating QRS) part rate

1 94 55 1.7 1 2 1 1:1 Total 71 2 94 48 1,9 1 2 1 1;1 Total 33 2 88 21 4,3 1 4 1 3:1 Atrial — 2 83 27 3,0 1 3 1 2:1 Total — 3 115 41 2,8 1 3 1 2:1 Ventricular 3 115 28 4.1 1 4 1 3:1 Total 112 4** 136 75 1.8 1 2 1 1:1 Ventricular 83 2 83 Varying Vary ng Varying Total — Marked sinus arrhythmia was present in all electrocardiograms No pericardiocentesis, patient treated with Furosemide

V^R

Figure 7, Case 2 Varying electrical alternans. seen between the normal and alternating (Figure 7). Conduction defects were not complexes, and the alternating com­ observed in the tamponade group. The plexes differed greatly from each other duration of the QRS did not vary greatly,

175 Niarchos neither between the normal and alternat­ TABLE V. DURATION OF THE QRS ing complexes, nor between the normal (SECONDS) IN THE PATIENTS WITH complexes, before and after pericar­ TAMPONADE BEFORE AND AFTER diocentesis (Table V). PERICARDIOCENTESIS Before pericardiocentesis After Radiological Findings Case Lead Normal Alternating Normal Cardiomegaly was present in all pa­ No. QRS QRS QRS tients ofthe series (Figures 8 and 9), and 1 11 0,10 0.08 0.06 the cardiothoracic ratio and cardiac 2 1 0.08 0.10 — 2 V, 0.08 0.10 0.12 silhouette volume were above normal in 2 V-, 0.06 0.08 — all. Both were greater in the patients with 3 V, 0.08 0.08 0.08 4 V, 0.06 0.06 0.08 cardiac tamponade. In particular the mean cardiothoracic ratio in the tam­ ponade and effusion group were 0.69 and ponade cases (480 mis in case 2, and 620 0.59 respectively, t = 4.01, p< .01; the mis in case 3), than in those with effusion mean cardiac silhouette volume was 735 (300 mis in case 6, and 270 mis in case 7). ml/m^ in the tamponade and 620 ml/m^ in Necropsy confirmed the diagnosis of the effusion group, t = 2.77, p <.05. Both secondary carcinomatous pericarditis in differences are significant. cases 2 and 3, and that of acute myocar­ dial infarction in cases 6 and 7.

Necropsy Discussion Necropsy was performed in four pa­ tients, two with tamponade and two with Incidence and Etiology of Electncal Alter­ effusion. Hemorrhagic pericardial fluid nans was found in all of them, but the amount A review of the literature reveals that of fluid was much greater in the tam- electrical alternans is a rare electrocar-

Figure 8, Case 1 Cardiomegaly (A) due to pericardial effusion; total electrical alternans was present with A, but it disappeared in B after pericardiocentesis of 30 mis of fluid and Furosemide administration; film B was taken four days after A.

176 Electrical Alternans in Cardiac Tamponade

The clinical, radiological and other laboratory findings of this study support the view that total electrical alternans in a patient with pericardial effusion is diag­ nostic of pericardial tamponade, since the abnormality was present only in pa­ tients with massive pericardial effusion and it disappeared after aspiration of var­ ying amounts of pericardial fluid. The disappearance ofthe alternans coincided with clinical improvement and reduction of the heart silhouette on the chest film. To my knowledge, electrical alternans due to either cardiac tamponade after acute myocardial infarction, or to mas­ sive pericardial effusion (hydropericar­ dium) complicating celiac disease has not been previously described. Other causes are listed in Table VI. Figure 9, Case 3 Massive pericardial effusion before pericar­ Mechanism of Electrical Alternans diocentesis; it coincided with various types of alternans, e.g. total, exact, 2:1, and 3:1. Two theories have been proposed to explain the mechanism of electrical al­ diographic abnormality, since its inci­ ternans when due to pericardial effusion. dence has been estimated as between 1 The electrocardiographic findings of this in 1,212 tracings" and 1 in 10,000." Up to study do not support the view that the date about 75 cases including the present alternans is due to a cyclic aberrant con­ four have been reported in the duction, induced by disturbances ofthe literature.In two-thirds of the re­ bioenergetic behavior of the myocar­ ported cases the electrical alternans was dium or by alternation in the refractory due to cardiac tamponade caused by phase ofthe conduction tissue.^'" In our malignant hemopericardium or to mas­ cases, no conduction defects were seen sive pericardial effusion. and the duration of the alternating QRS

TABLE VI. ETIOLOGY OF ELECTRICAL ALTERNANS

Cardiac tamponade Malignant hemopericardium Massive pericardial effusion due to: Tuberculous pericarditis Suppurative pericarditis Idiopathic pericarditis Uremia Acute myocardial infarction Constrictive pericarditis Congestive cardiac failure Rheumatic heart disease Ischemic heart disease Myocarditis Hypertension ?Congestive cardiac failure Pneumonectomy Tension pneumothorax*

*Niarchos, A. P., unpublished.

177 Niarchos

did not differ significantly from that ofthe by fluid, from left to right and vice versa normals (Table V). On the contrary the (Figure 3). When the heart is close to the present electrocardiographic findings right chest leads Vi and V2 a large QRS lend support to the theory which pre­ (QRSr) is recorded; when in the middle sumes exaggerated anatomic motion of the recorded complex (QRSm) is small, the heart within the pericardial sac en­ because the heart is surrounded byfluid; larged by massive effusion. Indeed, sev­ and when the heart is close to the left eral types of exaggerated cardiac motion chest wall, the recorded QRS (QRSl) is have been demonstrated in patients with larger than the QRSm, but smaller as pericardial effusion and total electrical al­ compared with the QRSr because it is ternans by various methods. Price and recorded from a distance. In lead Ve the Dennis^" have seen two types of cardiac opposite sequence of events takes place. movement in one patient with malignant In the middle chest leads (V3, V4 and VB) pericardial effusion during cineangiog­ the QRSr is equal to the QRSl because raphy; an anteroposterior pendulum-like both are recorded more or less from an movement and a periodic rotatory oscil­ equal distance from the middle. The vari­ lation. Feigenbaum et aV studied six pa­ ation of the QRS size in the posterior tients with pericardial effusion with ul­ leads only, as seen in case 1, can be ex­ trasound. In all an increased anteropos­ plained on the same basis but assuming terior movement was present, with a 3 cm that the heart is moving along an an­ excursion of the heart; electrical alter­ teroposterior plane. The observed varia­ nans, however, was present only in two tion in heart rate/alternans rate ratios 2:1, of them. Similarly an anteroposterior 3:1 and 4:1 (Table IV) can be explained cardiac movement has been demon­ by assuming that the frequency of the strated by Usher and Popp" on echocar­ cardiac cyclic motion is one-half, one- diograms in two patients. The frequency third and one-fourth respectively of the ofthe cardiac motion was either one-half heart rate (Figures 3, 4 and 5). Likewise a or equal to the frequency of the heart cardiac motion with varying frequency rate; total electrical alternans was pres­ and plane could account for the varying ent only when the frequency ofthe heart alternans. motion was one-half the frequency ofthe heart rate. In addition total electrical al­ The reason for an absent cardiac mo­ ternans has been produced experimen­ tion, orfora cardiac motion assuming the tally by using a laboratory model of an same frequency versus one-half, one- excised, perfused rabbit heart sus­ third or one-fourth of the frequency of pended in a electrolyte fluid-filled spher­ the heart rate, is not known. The factors ical chamber.^ Of 46 hearts thus pre­ which probably determine the frequency pared, 11 had one or more periods of and form of cardiac motion are the heart pendular oscillatory movement; the fre­ rate, the pericardial pressure, the volume quency, duration, amplitude and plane and viscosity of the pericardial fluid, a ofthe oscillations were either constant or fixed aortic root by secondary deposits, tended to vary; in addition, a twisting the rigidity and configuration of the motion was occasionally seen. Total elec­ pericardial sac, and the mobility of the trical alternans was present when the fre­ pendulum-like heart within the pericar­ quency ofthe cardiac motion was half the dial sac.^'^" A combination of at least heart rate. The variation in size of the three factors is probably necessary to alternating QRS complexes as seen in the produce the type of heart motion that is present cases can be explained by ac­ associated with electrical alternans, since cepting the view that the heart is oscillat­ the presence of two of them (Tables I and ing within the pericardial sac distended 11), did not produce alternans in the effu-

178 Electrical Alternans in Cardiac Tamponade

sion group of patients. It seems from the tion is present but not in a regular present and previously reported cases mathematical order (Figure 4), the term that slow accumulation, large volume "varying electrical alternans" can be and malignant hemorrhagic fluid are used. Furthermore alternans can be pre­ most commonly associated with electri­ sent only either in the anterior (anterior cal alternans,^'"'"'^* although the ab­ alternans) or posterior leads (posterior normality has been reported in associa­ alternans). It is worth remembering that tion with non-hemorrhagic pericardial electrical alternans is not a cause of dis­ fluid (Table VI). It has been suggested turbance of the cardiac rhythm.Nor that electrical alternans is present only should it be confused with pulsus alter­ when the heart rate is 100 per minute or nans, although the two have rarely occur­ greater," but this is not confirmed in this red concurrently. study, as alternans was present with heart rates below 100 per minute (Figure 5), and Total and most commonly ventricular it disappeared after pericardiocentesis, electrical alternans, when due to pericar­ while the heart rate remained above 100 dial effusion, are diagnostic of impend­ per minute (Figure 4). This has been ing or established cardiac tamponade. documented by others." The pericardial Similarly 2:1, 3:1 and varying electrical pressure probably does not play an im­ alternans are indicative of massive effu­ portant role in the genesis of the alter­ sion or tamponade. All four types of al­ nans, since bradyarrhythmias and not ternans should be considered an indica­ electrical alternans have been reported tion for pericardiocentesis, which can be to occur in acute cardiac tamponade,"'" a life-saving procedure when the effusion although increased pericardial pressure is not caused by malignancy. The prog­ would probably distend and alter the nosis of malignant hemopericardium is configuration of the pericardial sac, in­ grave, since most of the reported cases creasing thus the arc of the cardiac (and two from this series) died within a motion."* few days after its onset, despite tempor­ ary improvement and disappearance of Classification and Prognosis the alternans following pericardiocen­ Electrical alternans has been described tesis. in the past as atrial, ventricular or total, Acknowledgments according to the alternating portion of the electrocardiogram. By definition the I am grateful to the consultants of the term should be used in order to describe Liverpool Regional Hospital Board and the well known 1:1 or exact electrical al­ United Liverpool Hospitals who allowed ternans (Figures 3 and 5). It is clear, how­ me to use data from patients under their ever, from this study (Table IV; Figures 6 care, and to Dr. N. Coulshed ofthe Liver­ and 7), that not only every second, but pool Regional Cardiac Centre, for per­ also every third or fourth complex can mission to use the results of the cardiac alternate; the term 2:1 and 3:1 electrical catheterization. alternans respectively is suggested, and can be either ventricular or total. In addi­ Addendum tion, when marked variation in QRS mor­ Since the submission of this paper phology is present (Figure 7), or alterna­ U-wave alternans has been reported.^'

179 Niarchos

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