Abstract
Purpose
In acute myocardial infarction (AMI) treated by primary percutaneous coronary intervention (PCI), there is a direct relationship between myocardial damage and consequent left ventricular (LV) functional impairment. It is however unclear whether there is a safety threshold below which infarct size does not significantly affect LV ejection fraction (EF). The aim of this study was to evaluate the relationship between infarct size and LVEF in AMI patients treated by successful PCI using a specific statistical approach to identify a possible safety threshold.
Methods
Among patients with recent AMI submitted to perfusion gated single photon emission computed tomography (SPECT) to define the infarct size, the data of 427 subjects with sizable infarct size were considered. The relationship between infarct size and LVEF was analysed using a simple segmented regression (SSR) model and an iterative algorithm based on robust least squares (RLS) for parameter estimation.
Results
The RLS algorithm detected two break points in the SSR model, set at infarct size values of 11.0 and 51.5 %. Because the slope coefficients of the two extreme segments of the regression line were not significant, by constraining such segments to zero slope in the SSR model, the lower break point was identified at infarct size = 8 % and the upper one at 45 %.
Conclusion
Using a rigorous statistical approach, it is possible to demonstrate that below a threshold of 8 % the infarct size apparently does not affect the LVEF and therefore a safety threshold could be set at this value. Furthermore, the same analysis suggests that the relationship between infarct size and LVEF impairment is lost for an infarct size > 45 %.
Similar content being viewed by others
References
Burns RJ, Gibbons RJ, Yi Q, Roberts RS, Miller TD, Schaer GL, et al. The relationships of left ventricular ejection fraction, end-systolic volume index and infarct size to six-month mortality after hospital discharge following myocardial infarction treated by thrombolysis. J Am Coll Cardiol 2002;39:30–6.
Sciagrà R, Imperiale A, Antoniucci D, Migliorini A, Parodi G, Comis G, et al. Relationship of infarct size and severity versus left ventricular ejection fraction and volumes obtained from 99mTc-sestamibi gated single-photon emission computed tomography in patients treated with primary percutaneous coronary intervention. Eur J Nucl Med Mol Imaging 2004;31:969–74.
Ndrepepa G, Mehilli J, Martinoff S, Schwaiger M, Schömig A, Kastrati A. Evolution of left ventricular ejection fraction and its relationship to infarct size after acute myocardial infarction. J Am Coll Cardiol 2007;50:149–56.
Sciagrà R, Parodi G, Migliorini A, Memisha G, Antoniucci D, Pupi A. Evaluation of the influence of age and gender on the relationships between infarct size, infarct severity, and left ventricular ejection fraction in patients successfully treated with primary percutaneous coronary intervention. J Nucl Cardiol 2010;17:444–9.
Pride YB, Appelbaum E, Lord EE, Sloan S, Cannon CP, Sabatine MS, et al. Relation between myocardial infarct size and ventricular tachyarrhythmia among patients with preserved left ventricular ejection fraction following fibrinolytic therapy for ST-segment elevation myocardial infarction. Am J Cardiol 2009;104:475–9.
Christian TF, Schwartz RS, Gibbons RJ. Determinants of infarct size in reperfusion therapy for acute myocardial infarction. Circulation 1992;86:81–90.
Miller TD, Christian TF, Hopfenspirger MR, Hodge DO, Gersh BJ, Gibbons RJ. Infarct size after acute myocardial infarction measured by quantitative tomographic 99mTc sestamibi imaging predicts subsequent mortality. Circulation 1995;92:334–41.
Christian TF, Berger PB, O’Connor MK, Hodge DO, Gibbons RJ. Threshold values for preserved viability with a noninvasive measurement of collateral blood flow during acute myocardial infarction treated by direct coronary angioplasty. Circulation 1999;100:2392–5.
Stone GW, Dixon SR, Grines CL, Cox DA, Webb JG, Brodie BR, et al. Predictors of infarct size after primary coronary angioplasty in acute myocardial infarction from pooled analysis from four contemporary trials. Am J Cardiol 2007;100:1370–5.
Sciagrà R, Parodi G, Sotgia B, Antoniucci D, Pupi A. Determinants of final infarct size and incidence of aborted infarction in patients treated with primary coronary intervention and adjunctive abciximab therapy. Nuklearmedizin 2008;47:56–61.
Miller TD, Sciagrà R, Gibbons JJ. Application of technetium-99m sestamibi single photon emission computed tomography in acute myocardial infarction: measuring the efficacy of therapy. Q J Nucl Med Mol Imaging 2010;54:213–29.
Pride YB, Giuseffi JL, Mohanavelu S, Harrigan CJ, Manning WJ, Gibson CM, et al. Relation between infarct size in ST-segment elevation myocardial infarction treated successfully by percutaneous coronary intervention and left ventricular ejection fraction three months after the infarct. Am J Cardiol 2010;106:635–40.
The TIMI Study Group. The Thrombolysis in Myocardial Infarction (TIMI) trial. Phase I findings. N Engl J Med 1985;312:932–6.
O’Connor MK, Hammel T, Gibbons RJ. In vitro validation of a simple tomographic technique for estimation of percentage myocardium at risk using methoxyisobutyl isonitrile technetium 99m (sestamibi). Eur J Nucl Med 1990;17:69–76.
Germano G, Kiat H, Kavanagh PB, Moriel M, Mazzanti M, Su HT, et al. Automatic quantification of ejection fraction from gated myocardial perfusion SPECT. J Nucl Med 1995;36:2138–47.
Sciagrà R, Berti V, Genovese S, Pupi A. Reliability of myocardial perfusion gated SPECT for the reproducible evaluation of resting left ventricular functional parameters in long-term follow-up. Eur J Nucl Med Mol Imaging 2010;37:1722–9.
Muggeo V. Estimating regression models with unknown break-points. Stat Med 2003;22:3055–71.
Hampel F, Ronchetti E, Rousseeuw P, Stahel W. Robust statistics: the approach based on influence functions. New York: Wiley; 2005.
Ibrahim T, Nekolla SG, Hörnke M, Bülow HP, Dirschinger J, Schömig A, et al. Quantitative measurement of infarct size by contrast-enhanced magnetic resonance imaging early after acute myocardial infarction: comparison with single-photon emission tomography using Tc99m-sestamibi. J Am Coll Cardiol 2005;45:544–52.
Kim HW, Farzaneh-Far A, Kim RJ. Cardiovascular magnetic resonance in patients with myocardial infarction: current and emerging applications. J Am Coll Cardiol 2009;55:1–16.
Nichols K, Santana CA, Folks R, Krawczynska E, Cooke CD, Faber TL, et al. Comparison between ECTb and QGS for assessment of left ventricular function from gated myocardial perfusion SPECT. J Nucl Cardiol 2002;9:285–93.
Hambye AS, Vervaet A, Dobbeleir A. Variability of left ventricular ejection fraction and volumes with quantitative gated SPECT: influence of algorithm, pixel size and reconstruction parameters in small and normal-sized hearts. Eur J Nucl Med Mol Imaging 2004;31:1606–13.
Ford PV, Chatziioannou SN, Moore WH, Dhekne RD. Overestimation of the LVEF by quantitative gated SPECT in simulated left ventricles. J Nucl Med 2001;42:454–9.
Seber GAF, Wild CJ. Nonlinear regression. New York: Wiley; 2003.
Conflicts of interest
None.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Sciagrà, R., Cipollini, F., Berti, V. et al. Detection of infarct size safety threshold for left ventricular ejection fraction impairment in acute myocardial infarction successfully treated with primary percutaneous coronary intervention. Eur J Nucl Med Mol Imaging 40, 542–547 (2013). https://doi.org/10.1007/s00259-012-2329-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00259-012-2329-z