T HE heart is often ;dCectcd in diphtheria with rcsul?a~!t: c!cctroe;~r(~iogr~pllic cl~nges. This paper is concerned wit.h the changes occurring in. adults only. In this global war, many 01 our soldiers are sfatior:txi in arean where diph-

theria is endemic, amongst the native. jmpularion. SOlilC! of ous troopa coIls~?~~ quently dcvclop diphtheria. lt is 1.1~~ practice of this )lospital !~ene~al. hos- pital overseas) to take serial e~c!~~ll.nca~dioarltnls oli ;r:l bases 01’ diphthel*ia throughout the course of the disease.

Twelve cases of diphtheria ilax-‘C been diagnost:c! and treat4 ; eloctrc~- cardiographic changes wevc found ill two, an incidencr UC 1.6.5 per cent cardiac j nvolvement. Egglest.onl described T-wuvc changes {si:u i tar I.a .t.his series) as the most frequently observed &:ct~~nc;r rdiographic nlt.cr;liion in 16 par cent. of his cases. I>uring the stage of inversion, the T-wavl ,, changes may so closrly simulate the inverted “coronary T wave” of myocclrdiaf ini’arcoion that this error in diagnosis can be made unless abteution is pahi !o th S-1‘ i,lterv:ll.

Normal CmPlBX E!u?ly 5-P depression Later 5 wav lnYsrsion

(a) b!yocfudial infarct1czl due to coronary occlusion

Normal conplex Early S-T elevation Later T- waw inversion

Fig. I.-Schcnmtic rlrawing illustrating thi: 1yp1m1 S-T and T-~rrvc; changes in (fz) dbhthcri- tic myocarditis and (I.Z) myo-orardid inParction clue! t.0 c:oronn~- occlusl0n.

The earliest clectrocardiogral!hic: chiulae observed in diphtheritic! rnyocarditis (Kg. 1) is a deprcssiou of t.he S-T interval. The T wave t.hen becomes lower

in amplitude, isoelectric, diphssia, and finally inverted. The S-T interval al- ways remains slightly depressed. This is in direct contrast to the ST interval in myocardial infarction, where, after the initial marked elevation of the S-T interval and the subsequent inversion of the T wavq the S-T interval is always isoelectric or slight.ly above the isoelectric lint*. ---.-

REPORT OF CAiSES

CASE 1.-A man, aged 22 years, complained of a SOW throat and generalized aches

and pains four days before admission to the hospital. Physical examination revealed what appeared to be an acute follicular tonsillitis which responded promptly to sulfadiazine by

mouth. Five days later, while convalexing, he dercloprii a sore throat, headache, and temperature of 191.S” F. Throat culture xx lktive for Klehs-LSBer bacilli and 40,000

units of diphtheria antitoxin were admini~terod. Eleclroc~artliogram (E’ig. 2) taken on

5::::::: z::::::: :::::::: ::::::::, . . . . . . . . . . . . . . . . ‘::::“I i::::::: c:::::::, ‘!::::!: . . . . . . . . . . . _ :iiz;:z I’::::!:, . . . ..i VT::.::: a:\.. - . . . .

B,\I,I, : DII’HTHEXITIC MYO(‘hKDlTIS

mained symptom free. It cannot be stated with rertaintv whether or not this patient had

diphtheria when he was first admitted to the hospit,al with what appeared to be an acute follicular tonsillitis. In view of the fact that there were other cases of diphtheria in the

hospital at the time, it is possible and likely that the iirst evidence of “sore throat” wHS

due to diphtheria.

CASE Z.-A man, aged 37 years, was admitted to the hospital on J&n. 24, 1944, with nasopharyngitis. A routine eleetroctlrdiogram was normal. \Vhile convalescing, he developed

a perianal cellulitis, secondary to an internal hemorrhoid. This was treated conservatively.

On Feb. 19, 1944, he had an epist,asis. Five days later (F‘cb. 24, 1944) he complained of a

sore throat and the next day was found to have a dirty, o vray membrane in the left nosIri1

and an early membrane formation on both tonsils. Temperature was 103.6” l?. A clinical

diagnosis of diphtheria was made, nose and throat cultures were taken, and the patient was transferred to the isolation service and given ,JO,OOO units of diphtheria antitoxin, intramuscularly. Nose and throat cultures were positive for Klebs-LGffler bacilli. The

first electrocardiogram, taken Feb. 27, 194--I, two days after the appearance of the mem

brdne, was normal (Fig. 3). Temperature became normal on March 2, 1941, and the mem-

brane disappeared on March 5, 1914. Nose and throat cultures, taken on March 9, and March 11, 1944, were still positive. A small follicle appeared on the left tonsil on March

12, 194-l, and another dose of diphtheria antitoxin, $O,O!lO units, were given intramuseu-

larly. An electrocardiogram, taken the next day, sixteen days after the appearance of a membrane, showed the first deviation from the normal, a depression of the S-T interval in

Lead I and elevation in Lead IV. Electrocardiogram, taken on March 19, 1944, showed

typical changes seen in diphtheritic myoearditis. The only clinical cardiac finding at this time was a persistent tachycardia with a rate of 120 per minute. Blood pressure was

120/70 and teleroentgenogram was normal. ‘I’he patient, then developed a classical, marked

peripheral neuritis in all extremities with marked motor weakness. Marked apprehension

and nervousness were present, and there was beginning weight loss. The nervousness, tachycardia, and weight loss suggested the clinical picture of hypert,hproidism. Unfor-

tunately, there was no machine available to determine the basal metabolic rate. The

pa.tient was given a therapeutic test with lug01 solution and, within a week, the pulse rate was normal, nervousness disappeared, and appetite returned. Lug01 ‘s solution was adminis-

tered for anot,her ten days and then discontinued. Serial e-lectrocardiograms (Pig. 3) show

the typical changes observed in this case with a return to an almost, normal cur\-e. The

peripheral neuritis gradually improved and the patient was able to walk and get around

before being evacuated to the zone of the int,erior.

COMMENT

The electrocardiographic changes observed in both Cases described would indicate that there was severe and extensive myocardial involvement. Rt no

time did these patients have any complaints referable to the cardiovascular system and, at no time, were there any clinical findings to suggest, involvement of the heart. In both cases, the changes were reversible and shifting from day to day, suggesting that the changes observed are “tosic” in origin and not

due to any structural damage to the heart muscle.

COSCLTJSIONS

1. The electrocardiographic changes observed in two cases of diphtheria in adults are described. These changes conform to a type that is easily differen- tiated from those observed in myocardial infarction due to coronary artery occlusion.

2. The S-T int,erval is always depressed in diphtheritic myocarditis. 3. The changes are reversible and “shifting.” 4. These effects are probably toxic in origin in di.phtheritic myocarditis. 5. There was no clinical evidence of heart disease in either case described.

REFERENCE

1. Burkhardt, E. A., Eggleston? C., and Smith, L. W.: Electrocardiographic Changes and Peripheral Nerve Palsies in Toxic Diphtheria, Am. J. $1. SC. 195: 301, 1938.