The electropathology behind the pseudonormalisation of the T wave may be explained by a superposition of acute ischaemic effects on the action potential of myocardial cells on top of chronic ischaemic effects. Pseudo normalization of the repolarization during transient episodes of myocardial ischemia. Am Heart J 1977; 94: 390-1.
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Page/Link:Page URL:HTML link:The Free Library. Retrieved Aug 31 2019 fromABSTRACTObjective: Spontaneous pseudonormalization (PN) is a unique 12-leadelectrocardiography (ECG) finding which has been reported to beassociated with severe, transmural myocardial ischemia. To date, apaucity of data exists about the incidence and clinical characteristicsof patients with PN. Therefore the aim of this study was to investigatethe incidence and the electrocardiographic, echocardiographic, andangiographic characteristics of patients with PN.Methods: Clinical, laboratory, electrocardiographic,echocardiographic, and angiographic characteristics of 12 consecutivepatients with PN on 12-lead ECG (Group 1) were compared with patients(Group 2, n = 28) presenting with acute coronary syndrome (ACS)associated with ST-T wave changes without PN.Results: All patients presented with chest pain.
The incidence ofPN among patients presenting with ACS was 1%. Pseudonormalization waspresent in precordial leads in 11 and in inferior leads in 1 patient.Nine out of 12 (75%) patients in Group 1, 16 out of 28 (57%) patients inGroup 2 had elevation of cardiac enzymes compatible with acutemyocardial infarction. Severely narrowed or totally occluded ischemiaand/or infarction-related coronary arteries were present in all patientsin Group 1, in 20 (71%) patients in Group 2. Three patients in Group 1and one patient in Group 2 had coronary artery thrombus formation. Group1 patients had worse coronary collateral grading in comparison to Group2 patients.
Conclusion: Pseudonormalization is a rare entity and it istypically associated with severely narrowed or totally occluded coronaryarteries along with thrombus formation, and poor coronary collateraldevelopment. (Anadolu Kardiyol Derg 2007: 7 Suppl 1; 175-7)Key words: pseudonormalization, electrocardiography, acute coronarysyndrome, echocardiography, coronary angiographyIntroductionSpontaneous pseudonormalization (PN) is a unique 12-leadelectrocardiography (ECG) finding which has been reported to beassociated with severe, transmural myocardial ischemia (1-4). To date, apaucity of data exists about the incidence and clinical characteristicsof patients with PN (1). Therefore, the aim of this study was toinvestigate the incidence and the electrocardiographic,echocardiographic, and angiographic characteristics of patients with PN.MethodsStudy populationPatients presenting with acute coronary syndrome (ACS) with PN on12-lead electrocardiogram (ECG) (Group 1) were prospectively included inthe study, between July 2003 and July 2006. Clinical, laboratory,electrocardiographic, echocardiographic, and angiographiccharacteristics of this group was compared with patients presenting withACS associated with ST-T wave changes without PN (Group 2). Patientswith completely normal coronary arteries were excluded from the study.Data acquisitionEvery patient had serial 12-lead ECGs, serial serum creatine kinase(CK)-MB, serum cardiac troponin I measurements, transthoracicechocardiography, and coronary angiography.12-lead surface ECGEvery patient had 12-lead ECG on admission, and during and after aneach episode of chest pain. Coronary angiographySelective coronary angiographies were performed in all patients.Atherosclerotic burden was measured by the modified Gensini score oncethe patient was diagnosed with coronary artery disease (8).
Developmentof coronary collaterals (collateral grading) was assessed by Rentropclassification (9).Statistical analysisValues were expressed as mean + or - SD. Characteristics ofgroups were compared using the unpaired Student's t-test and p0.05). Elevation of cardiac enzymes compatible withacute myocardial infarction was present in 9 out of 12 patients in Group1, and in 16 out of 28 patients in Group 2 (p0.05). Severelynarrowed (90% to 99%, n = 10) or totally occluded (n = 2) ischemiaand/or infarction-related coronary arteries were present in all patientsin Group 1, and in 20 patients (71%) in Group 2 (p0.05).
Threepatients (25%) in Group 1 and 1 patient (3%) in Group 2 had coronaryartery thrombus formation. Group 1 patients tended to have better LVejection fractions (52 + or - 13% versus 47 + or - 12%, p = 0.25),better wall motion index (0.16 + or - 0.29 versus 0.5 + or - 0.74, p= 0.12), and less atherosclerotic burden (91 + or - 83 versus 144 +or - 105, p = 0.1) in comparison to Group 2 patients. Group 1 patientshad less coronary collateral development (0.25 + or - 0.6 versus 1.04+ or - 1.3, p = 0.015) in comparison to Group 2 patients (Table 1).DiscussionThe cellular, electrocardiographic, and electrophysiologicalmechanisms of PN are unknown. Previous studies have shown that earlynegative T waves in patients with ST segment elevation myocardialinfarction are due to a recent transmural myocardial ischemia ratherthan active ischemia which is consistent with the data that recurrencesof spontaneous ischemia can result in transient ST segment re-elevationor pseudonormalization of T waves (10, 11). It is quite possible thatthe T wave inversions seen on the baseline 12-lead ECGs (taken in theabsence of active chest pain) in patients with ACS represent'myocardial stunning' rather than active ischemia.Angiographically, patients with PN typically have severely narrowed ortotally occluded ischemia/infarction-related coronary arteries withunstable plaques and thrombus formation. Furthermore, patients with PNmay have larger thrombus load and severely reduced coronary blood flow.In addition, underdeveloped coronary collaterals, as shown in our studypopulation, can be a contributing factor for myocardial ischemia.
As aresult, the mechanism for normalization may be the algebraic sum of theextent of ST segment elevation and the amplitude of the T waves of acutemyocardial ischemia plus the extent of preexisting ST segment depressionand the degree of T wave inversion, to result in isoelectric ST segmentand upright T wave (1, 12, 13).Pseudonormalization of T waves can be spontaneous ornon-spontaneous. Non-spontaneous PN of T waves have been frequentlydescribed in certain clinical conditions such as during coronaryangioplasty, exercise stress testing, and dobutamine echocardiography(14-19). These studies reported that the PN of T waves predicts recoveryof regional contractile function after anterior wall myocardialinfarction. However, the specificity and the sensitivity of this findingfor the presence or absence of myocardial ischemia are low.
On the otherhand, spontaneous PN is a relatively rare but a very specific findingfor severe myocardial ischemia among patients with ACS.In agreement with prior studies, we showed that spontaneous PN of Twaves indicate severe myocardial ischemia (1-5). Therefore, thesepatients should be treated on an urgent basis with aggressive medicaltreatment and percutaneous coronary intervention.Study LimitationsThe number of patients in Group 1 were limited due to the rarity ofPN. The plaque structure and the thrombus load can be better delineatedby using intravascular ultrasound and coronary angioscopy.ConclusionsPseudonormalization is a rare entity and it is typically associatedwith severely narrowed or totally occluded coronary arteries along withthrombus formation and poor coronary collateral development.
Patientswith PN tend to have better left ventricular function, wall motion indexand less atherosclerotic burden in comparison to patients with ACS butwithout PN.References(1.) Noble RJ, Rothbaum DA, Knoebel SB, McHenry PL, Anderson GJ.Normalization of abnormal T waves in ischemia. Arch Intern Med 1976;136: 391-5.(2.) Haiat R, Halphen C, Derrida JP, Chiche P.
Pseudonormalizationof the repolarization during transient episodes of myocardial ischemia.Am Heart J 1977; 94: 390-1.(3.) Goldberger AL. Hyperacute T waves revisited. Am Heart J 1982;104: 888-90.(4.) Haiat R. Pseudonormalization of repolarization: a sign ofacute myocardial ischemia.
Am Heart J 1983; 106: 171-2.(5.) Goldberger AL. Myocardial infarction: electrocardiographicdifferential diagnosis.
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St Louis: Mosby-Year Book; 1991.(6.) Bourdillon PD, Broderick TM, Sawada SG, Armstrong WF, Ryan T,Dillon JC, et al. Regional wall motion index for infarct and noninfarctregions after reperfusion in acute myocardial infarction: comparisonwith global wall motion index.
J Am Soc Echocardiogr 1989; 2: 398-407.(7.) Redfield MM, Jacobsen SJ, Burnett JC Jr, Mahoney DW, BaileyKR, Rodeheffer RJ. Burden of systolic and diastolic ventriculardysfunction in the community: appreciating the scope of the heartfailure epidemic. JAMA 2003; 289: 194-202.(8.) Gensini GG. A more meaningful scoring system for determiningthe severity of coronary heart disease. Am J Cardiol 1983; 51: 606.(9.) Rentrop KP, Cohen M, Blanke H, Phillips RA. Changes incollateral filling after controlled coronary artery occlusion by anangioplasty balloon in human subjects. J Am Coll Cardiol 1985; 5:587-92.(10.) Chierchia S, Brunelli C, Simonetti I, Lazzari M, Maseri A.Sequence of events in angina at rest: primary reduction in coronaryflow.
Circulation 1980; 61: 759-68.(11.) Figueras J, Cortadellas J, Rodes J, Domingo E, Castell J,Soler JS. Early negative T waves and viable myocardium in patients witha first ST-elevation acute coronary syndrome. J Electrocardiol 2005; 38:171-8.(12.) Di Diego JM, Antzelevitch C. Cellular basis for ST-segmentchanges observed during ischemia. J Electrocardiol 2003; 36: 1-5.(13.) Hlaing T, DiMino T, Kowey PR, Yan GX. ECG repolarizationwaves: their genesis and clinical implications.
Ann NoninvasiveElectrocardiol 2005; 10: 211-23.(14.) Zack PM, Aker UT, Kennedy HL. Pseudonormalization of T-wavesduring coronary angioplasty.
Cathet Cardiovasc Diagn 1987; 13: 191-3.(15.) Lavie CJ, Oh JK, Mankin HT, Clements IP, Giuliani ER, GibbonsRJ. Significance of T-wave pseudonormalization during exercise. Aradionuclide angiographic study. Chest 1988; 94: 512-6.(16.) Lombardo A, Loperfido F, Pennestri F, Rossi E, Patrizi R,Cristinziani G, et al. Significance of transient ST-T segment changesduring dobutamine testing in Q wave myocardial infarction. J Am CollCardiol 1996; 27: 599-605.(17.) Pizzetti G, Montorfano M, Belotti G, Margonato A, BallarottoC, Chierchia SL. Exercise-induced T-wave normalization predicts recoveryof regional contractile function after anterior myocardial infarction.Eur Heart J 1998; 19: 420-8.(18.) Schneider CA, Helmig AK, Baer FM, Horst M, Erdmann E, SechtemU.
Significance of exercise-induced ST-segment elevation and T-wavepseudonormalization for improvement of function in healed Q-wavemyocardial infarction. Am J Cardiol 1998; 82: 148-53.(19.) Ho YL, Lin LC, Yen RF, Wu CC, Chen MF, Huang PJ. Significanceof dobutamine-induced ST-segment elevation and T-wavepseudonormalization in patients with Q-wave myocardial infarction:simultaneous evaluation by dobutamine stress echocardiography andthallium-201 SPECT. Am J Cardiol 1999; 84: 125-9.Cem Ulucan, Oguz Yavuzgil, Meral Kayikcioglu, Levent Can, SerdarPayzin, Hakan Kultursay, Inan Soydan, Can HasdemirDepartment of Cardiology, Medical Faculty, Ege University, Izmir,TurkeyAddress for Correspondence: Can Hasdemir, MD, Department ofCardiology, Medical Faculty, Ege University, Izmir, Turkey Phone: +90232 390 4001 E-mail: [email protected] 1.
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