Is this heart broken?

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  • NUCLEAR CARDIOLOGY BULLET

    Is this heart broken?Mati Friehling, MD,a Bryan OConnell, MD,a William P. Follansbee, MD,b andPrem Soman, MD, PhDb

    We present the case of a woman presenting withchest pain that illustrates the importance of recognizingan atypical presentation of coronary artery disease inwomen, as well as the role of myocardial perfusionimaging in the differential diagnosis.

    Case presentation. A 54-year-old black womanpresented to the emergency department with atypicalchest pain and left shoulder and arm pain of 8 hoursduration. She was known to have bromyalgia and ananxiety disorder, with a recent exacerbation related todomestic unrest. Her risk factors for coronary arterydisease consisted of hypertension, hyperlipidemia,tobacco use, and a family history of myocardialinfarction.

    The 12-lead electrocardiogram at presentationshowed sinus bradycardia and T-wave inversion in theinferior and lateral leads. The cardiac troponin I levelwas elevated, at 0.5 g/L. Aspirin, -blocker, heparin,and intravenous nitrate therapy was initiated. Severalhours later, the patient had worsening chest discomfortassociated with diaphoresis, bradycardia, and nonsus-tained ventricular tachycardia. An electrocardiogramshowed more pronounced and extensive T-wave inver-sion (Figure 1), and the second troponin I level was 9.8g/L. Emergent cardiac catheterization was performedand revealed a left anterior descending coronary arterythat tapered distally, with luminal irregularity (50%diameter stenosis) in its midportion. The left circumexand right coronary arteries were normal (Figure 2).Contrast left ventriculography was remarkable for severeregional dysfunction localized to the left ventricular(LV) apex and the adjacent anterior and inferior walls,with hypercontractility of the basal portions of theventricle (Figure 3). A clinical diagnosis of takotsubocardiomyopathy, also referred to as transient LV apicalballooning or broken heart syndrome, was entertained.

    The cardiac troponin I level peaked at 32 g/L on serialtesting.

    A resting technetium 99m sestamibi myocardialsingle photon emission computed tomography (SPECT)scan was performed the next day. It revealed a severeperfusion abnormality involving the apex and the adja-cent anterior and inferior walls, with a complete absenceof Tc-99m sestamibi uptake (Figure 4). A rest thallium201/exercise Tc-99m sestamibi myocardial gated SPECTstudy was performed 2 months later and showed a largexed defect associated with regional dysfunction, essen-tially unchanged from the initial scan (Figure 5). Anechocardiogram obtained shortly thereafter showed per-sistent LV apical dyskinesis (Figure 6).

    Discussion. Several features of this patients ini-tial presentation were typical of takotsubo cardiomyop-athy. These include her gender, age, recent emotionaldistress, and severe regional LV dysfunction in theabsence of epicardial coronary obstruction. Takotsubocardiomyopathy, originally described in Japanese pa-tients, is being increasingly recognized in the Westernworld, including the United States, and is characterizedby acute, reversible LV apical dysfunction in the absenceof obstructive epicardial coronary disease.1 The preva-lence of this syndrome is reported to be 1% to 2% inpatients presenting with clinical features suggestive of anacute coronary syndrome. The majority of patients arepostmenopausal women,1,2 with the following featurescommon to most accounts: (1) chest symptoms, electro-cardiographic changes, and mild elevation in cardiacbiomarkers consistent with acute myocardial ischemia;(2) a temporal relationship to a recent stressful event,giving this condition its alternate name of broken heartsyndrome (some form of either emotional or physicalstress preceded onset in about 65% of cases); (3) regionaldysfunction localized to the LV apex, associated withhyperkinesis of the basal portions of the left ventriclewith normal epicardial coronary arteries (Takotsubo isJapanese for octopus trap or pot and refers to thecharacteristic shape of the dysmorphic left ventricle seenon the ventriculogram of patients with this syndrome);and (4) complete resolution of the regional dysfunctionin days to weeks after the acute event.2

    The pathogenesis of myocardial perfusion and func-tional abnormalities in takotsubo cardiomyopathy re-mains speculative. Proposed mechanisms include(1) coronary spasm, (2) LV dysfunction induced by

    From the Department of Internal Medicinea and Division ofCardiology,b University of Pittsburgh Medical Center, Pittsburgh,Pa.

    Reprint requests: Prem Soman, MD, PhD, MRCP(UK), Division ofCardiology, University of Pittsburgh Medical Center, Room A 429,Scaife Hall, 200 Lothrop St, Pittsburgh, PA 15213; somanp@upmc.edu.

    J Nucl Cardiol 2008;15:142-5.1071-3581/$34.00Copyright 2008 by the American Society of Nuclear Cardiology.doi:10.1016/j.nuclcard.2007.11.011

    142

  • elevated catecholamine levels, and (3) abnormal micro-vascular blood ow.2

    Although the initial presentation of this patientfavored the diagnosis of takotsubo cardiomyopathy,the severity of perfusion abnormality seen on herinitial resting Tc-99m sestamibi myocardial SPECTscan was indicative of a transmural acute myocardialinfarction (AMI) with the absence of signicant resid-

    ual myocardial viability. Although many prior reportsof myocardial perfusion imaging in patients withtakotsubo cardiomyopathy have noted resting perfu-sion abnormalities in areas of regional dysfunction,these have generally been mild, transient, and associ-ated with only minor elevations in cardiac troponinlevels. Severe perfusion abnormalities are distinctlyunusual, and the unifying feature of all reports is the

    Figure 1. Twelve-lead electrocardiogram showing ST-segment elevation and T-wave inversion inleads V2 through V6 and II, III, and aVF.

    Figure 2. Coronary angiogram showing a mild luminal irregularity (arrow) in the left anteriordescending artery without obstructive stenosis (A) and a normal right coronary artery (B).

    Figure 3. Left ventriculogram showing a dyskinetic LV apex (arrows) and hypercontractility of thebasal segments.

    Journal of Nuclear Cardiology Friehling et al 143Volume 15, Number 1;142-5 Is this heart broken?

  • recovery of regional function and perfusion on echo-cardiography or myocardial perfusion imaging (orboth) performed days to weeks after the acute presen-tation.3 When regional function and perfusion fail torecover, this indicates that an AMI has occurred, andthe diagnosis of takotsubo cardiomyopathy cannot beentertained. The nal diagnosis in our patient was

    transmural AMI, presumably due to spasm in the leftanterior descending coronary artery at the site of anonobstructive coronary plaque. Although delayedresolution of regional dysfunction has been reported inpatients with takotsubo cardiomyopathy and may the-oretically occur in the future in this patient, thepersistence of a severe apical perfusion abnormality

    Figure 4. Left, Resting Tc-99m sestamibi SPECT perfusion image showing a severe restingperfusion defect in the apical and inferoapical region. Right, The gated SPECT images show nobrightening of the apical region in the systolic image, indicative of regional dysfunction (absence ofmyocardial thickening). The other walls are brighter on the systolic images, indicative of normalregional function.

    Figure 5. Left, Follow-up myocardial SPECT scan (rest Tl-201/stress Tc-99m sestamibi) 2 monthslater, showing a persistent xed perfusion abnormality in the apical and inferoapical region. For eachview, the stress and rest images are displayed in the top and bottom rows, respectively. Right, Thegated SPECT images show no brightening of the apical region in the systolic image, indicative ofregional dysfunction (absence of myocardial thickening). The other walls are brighter on the systolicimages, indicative of normal regional function.

    144 Friehling et al Journal of Nuclear CardiologyIs this heart broken? January/February 2008

  • with the absence of Tc-99m sestamibi uptake at 2months indicates a low likelihood of functional recov-ery.

    The pathophysiology and presentation of acute cor-onary syndromes in women differ from the classicdescriptions in men. A signicantly larger proportion ofwomen presenting with an acute coronary syndromehave nonobstructed epicardial coronary arteries, as com-pared with men. Women also present more frequentlywith atypical symptoms and more often have nonST-segment elevation myocardial infarction. Despite themore frequent nding of nonobstructed epicardial coro-nary arteries, women with acute coronary syndromeshave similar or worse outcomes than men.4 Therefore ahigh index of suspicion for an acute coronary syndromeshould be entertained when women present with chestpain, even if the character of the pain and electrocardio-graphic changes are not typical. This case underscoresthe potential difculty of identifying acute coronarysyndromes in women.

    Acknowledgment

    The authors have indicated they have no nancial conictsof interest.

    References

    1. Sharkey SW, Lesser JR, Zenovich AG, Maron MS, Lindberg J,Longe TF, et al. Acute and reversible cardiomyopathy provoked bystress in women from the United States. Circulation 2005;111:472-9.

    2. Gianni M, Dentali F, Grandi AM, Sumner G, Hiralal R, Lonn E.Apical ballooning syndrome or takotsubo cardiomyopathy: a sys-tematic review. Eur Heart J 2006;27:1523-9.

    3. Ito K, Sugihara H, Kawasaki T, Yuba T, Doue T, Tanabe T, et al.Assessment of ampulla (Takotsubo) cardiomyopathy with coronaryangiography, two-dimensional echocardiography and 99mTc-tetro-fosmin myocardial single photon emission computed tomography.Ann Nucl Med 2001;15:351-5.

    4. Hochman JS, Tamis JE, Thompson TD, Weaver WD, White HD,Van der Werf F, et al. Sex, clinical presentation, and outcome inpatients with acute coronary syndromes. Global Use of Strategies toOpen Occluded Coronary Arteries in Acute Coronary SyndromesIIb Investigators. N Engl J Med 1999;341:226-32.

    Figure 6. Two-dimensional echocardiogram showing the apical 4-chamber view in diastole (left)and systole (right) obtained 2 months after the initial presentation. An apical aneurysm is seen(arrows).

    Journal of Nuclear Cardiology Friehling et al 145Volume 15, Number 1;142-5 Is this heart broken?