Menoufia Medical Journal

ORIGINAL ARTICLE
Year
: 2017  |  Volume : 30  |  Issue : 4  |  Page : 1214--1219

The relationship between electrocardiographic fish-hook sign and early diastolic left ventricular velocity in athletes


Mohamed Yahia 
 Department of Cardiology, Faculty of Medicine, Menoufia University, Shebin Elkom, Egypt

Correspondence Address:
Mohamed Yahia
Lecturer of Cardiology, Department of Cardiology, University of Menoufia
Egypt

Abstract

Objectives The aim of the present study was to find a relationship between ECG fish-hook sign and echocardiographic variables in football athletes. Background Early repolarization is a common finding among athletes. The notched or irregular J point is known as the fish-hook sign, and it is a pattern of early repolarization. Patients and methods The present cross-sectional study was conducted using 61, male football players who were recruited during precompetition medical assessments in June 2016. The study was carried out at the medical clinics of two sports clubs in the Kingdom of Saudi Arabia. Standard 12-lead resting ECG and two-dimensional echocardiography were performed for all participants. Results The mean age was 25.7 ± 4.47, the mean body surface area was 1.86 ± 0.11 cm2, the mean corrected QT interval was 408.7 ± 22.12 ms, the main left ventricular (LV) mass index was 104.9 ± 18.5 g/m2, and the main LV ejection fraction was 59.9 ± 4.53%. The fish-hook sign was present in 32 (52.4%) athletes. The presence of a fish-hook sign was not statistically different with respect to age, body surface area, QRS duration, corrected QT interval, and LV hypertrophy. Athletes with a fish-hook sign had higher early diastolic mitral annulus velocity (E') and lower E/E' compared with athletes who had no fish-hook sign (P < 0.05). Conclusion Athletes with a fish-hook sign had higher peak early diastolic mitral annular (E') velocity and lower E/E' compared with athletes who had no fish-hook sign.



How to cite this article:
Yahia M. The relationship between electrocardiographic fish-hook sign and early diastolic left ventricular velocity in athletes.Menoufia Med J 2017;30:1214-1219


How to cite this URL:
Yahia M. The relationship between electrocardiographic fish-hook sign and early diastolic left ventricular velocity in athletes. Menoufia Med J [serial online] 2017 [cited 2024 Mar 28 ];30:1214-1219
Available from: http://www.mmj.eg.net/text.asp?2017/30/4/1214/229240


Full Text



 Introduction



Training-related ECG changes include increased QRS complex voltage, early repolarization (ER), sinus bradycardia, prolonged PR interval, and the Wenckebach phenomenon[1]. ER is defined as a J-point elevation of greater than or equal to 0.1 mV in two adjacent leads and having either a slurred or a notched morphology[2]. ER is commonly found in athletes, and may take the form of an elevated, notched J-point with the appearance of a fish hook. The prevalence of J-point elevation among young athletes has been reported as 22%, which is higher than that observed in the general population[3]. ER in athletes may occur as a consequence of physiological resetting of the balance between sympathetic and parasympathetic tones, which ultimately regulates transmembrane ionic currents[4],[5]. In athletes, although the mechanism is uncertain, ER seems to decline with age or when training declines, and often changes or disappears during an exercise session or with increasing heart rate, suggesting a mechanism that is vagally mediated or sensitive to heart rate[6]. On the basis of data associating these factors with arrhythmic risk, ERs are classified into three types[7]: type 1, in which there is ST-segment elevation in the lateral precordial leads, is common among healthy male athletes and is usually benign; type 2 is associated with ER in the inferior or inferolateral leads and with a moderate level of risk; and type 3 is associated with ER in the inferior, lateral, and right precordial leads and with the highest relative risk, although the absolute risk of sudden death remains small[8]. The objective of this study was not to judge the arrhythmic risk of ER in athletes but to find a relationship between ECG fish-hook sign and echocardiographic parameters in football athletes.

 Patients and Methods



The present cross-sectional study was conducted on 61, male football players who were recruited during precompetition medical assessments in June 2016 in the Kingdom of Saudi Arabia. The study followed the principles of the Declaration of Helsinki, and was approved by our institution's local ethics committee. Written informed consent was obtained from all participants before their involvement. The study excluded individuals with known cardiovascular disease and those in whom any disease was detected during screening. Personal, family, and medical histories were taken, and height, weight, and resting vital signs were obtained.

Standard 12-lead resting electrocardiography

A standard, 12-lead, resting ECG was performed using a GE MAC 5500 HD EKG machine (8200 west tower avenue, milwaukee, Wisconsin, USA). After 10 min of quiet rest, individuals were studied in the supine position. ST segment and J-waves were analyzed. ST-segment elevation was defined as J-point elevation of at least 0.1 mV in the inferior (II, III, and augmented Voltage left Foot (aVF)), lateral (I, augmented Voltage left Arm (aVL), and V4-V6), or inferolateral (II, III, aVF, and V4-V6) leads. The presence of J-waves was defined as a positive 'hump-like' deflection immediately after a positive QRS complex at the onset of the ST segment. The fish-hook pattern was defined as a notched or irregular J-point. ER was defined as an elevation of the J-point by at least 0.1 mV in at least two leads and/or the presence of a J-wave (distinct notch)[9]. The mean heart rate, PR interval, QT interval, heart rate-corrected QT (QTc) interval (calculated using Bazett's formula), and QRS duration were measured. QRS amplitude was recorded as a continuous variable using the Sokolow–Lyon index[10].

Two-dimensional transthoracic echocardiogram

Two-dimensional (2D) transthoracic echocardiography was performed using a VIVID E9 machine (GE Healthcare, Chicago, Illinois, USA) equipped with a 1.9–3.8-mHz phased-array transducer. 2D imaging was performed from standard parasternal and apical views. The guidelines of the American Society of Echocardiography were applied when registering all 2D and conventional Doppler variables[11]. The average of three consecutive heart beats was used. Standard 2D and M-mode measurements included the left ventricular (LV) dimensions, interventricular septal thicknesses, and LV posterior wall thickness. The LV ejection fraction was estimated using the biplane method of disks (modified Simpson's rule), and the LV mass was calculated using the Deveraux formula[12]. The LV mass index was calculated by dividing LV mass by body surface area (BSA). The reference upper limits of normal LV mass linear measurements are 95 g/m 2 in women and 115 g/m 2 in men. The diameter and area of both left and right atria were measured. Tricuspid annular plane systolic excursion was measured by M-mode echocardiography of the lateral tricuspid annulus in the apical four-chamber view.

The diastolic function of the LV was assessed by determining the velocities of early (E) and late (A) diastolic transmitral flow, the ratio between early and late peak pulsed Doppler velocities (E/A), and pulmonary vein flow velocities[13]. In addition, the isovolumetric relaxation time and deceleration time of the E-wave were measured.

Pulsed-wave tissue Doppler imaging (TDI) analysis was conducted on apical images acquired with greater than 100 frames. The 2-mm pulsed Doppler sample volume was placed in lateral and septal mitral annuluses. The diastolic components measured were peak systolic velocity (S), peak early diastolic velocity (E'), and peak late diastolic velocity (A'). Pulsed Doppler and TDI data were combined to calculate the E/E' ratio. All data were stored digitally, and post-hoc analyses were conducted by cardiologists blinded to study time points (EchoPac, version 7.0; GE Healthcare).

Statistical analysis

The data collected were tabulated and analyzed using SPSS (version 16 software; (SPSS Inc., Chicago, Illinois, USA). Categorical data are presented as numbers and percentages, and quantitative data are expressed as mean ± SD and ranges. χ2 tests or Fisher's exact tests were used to analyze categorical variables. Quantitative data were tested for normality using the Shapiro–Wilks test, assuming normality at P value greater than 0.05. If normality was proven, the Student's t-test was used. The accepted level of significance was 0.05, and therefore P value less than 0.05 was considered statistically significant.

 Results



This cross-sectional cohort study was conducted on 61, male football players who were recruited during precompetition medical assessments in June 2016. The mean age was 25.7 ± 4.47 (range: 20-36), and the mean BSA was 1.86 ± 0.11 cm 2 (range: 1.65-2.15 cm 2). The mean QRS duration was 96.7 ± 9.66 ms, the mean PR interval was 171 ± 23 ms, and the mean QTc interval was 408.7 ± 22.12 ms. ST-segment elevation was present in 43 (70.5%) players, inferior ST-segment elevation in nine (21%) athletes, lateral ST-segment elevation in 12 (28%), and inferolateral ST-segment elevation in 22 (51%) players. The fish-hook sign was present in the ECG of 32 (52.4%) athletes. ECG voltage criteria for LV enlargement were present in 10 (16.4%) athletes. Participants were classified into two groups according to presence or absence of the fish-hook sign in their ECGs. Presence of the fish-hook sign was not statistically significantly related to age, BSA, QRS duration, heart rate-QTc interval, or LV hypertrophy [Table 1] and [Figure 1] and [Figure 2].{Table 1}{Figure 1}{Figure 2}

Conventional echocardiography was performed for all athletes. The main LV mass index was 104.9 ± 18.5 g/m 2, and the main LV ejection fraction was 59.9 ± 4.53%. Five (8%) players had increased LV mass index. Athletes with the fish-hook sign had higher peak early diastolic mitral annular septal E' velocities compared with athletes who did not (12.2 ± 2.42 vs. 10.8 ± 2.15 cm/s, P = 0.027). In addition, those with the fish-hook sign had higher mitral annular lateral E' velocity than those who did not (19.0 ± 2.75 vs. 14.4 ± 2.83 cm/s, P = 0.013). Finally, those with the fish-hook sign had lower E/E' than those who did not (5.9 ± 1.28 vs. 7.04 ± 1.72, P = 0.008). There were nonsignificant differences in LV dimensions, atrial dimensions, peak mitral inflow velocity (E and A waves), mitral deceleration time, and mitral valve E/A [Table 2] and [Table 3].{Table 2}{Table 3}

 Discussion



Exercise is a strong stimulus for cardiac adaptation, and there is a large body of evidence showing that exercise training causes physiological and morphological cardiac alterations[14]. As ECG is a highly appropriate preparticipation examination for athletes, it is important to differentiate ECG patterns related to pathology from those related to normal variants.

ER is a common ECG finding in athletes[15], and has been used to mark QRS-T changes in ECGs[16]. The foremost writings on the subject define ER as a J-point elevation on the ECG of greater than or equal to 0.1 mV in two adjacent leads, which appears either as a terminal QRS slurring during the transition from the QRS segment to the ST segment or as a positive, notched deflection on the terminal QRS complex followed by a concave upward ST-segment elevation. This notched or irregular J-point is known as a fish-hook sign and indicates ER.

Previous studies have demonstrated that ER is commonly found in athletes[3],[17]. In the present study, about 70% of the participants showed ER, and 52% showed the fish-hook sign. In the present study, the presence of the fish-hook sign did not differ significantly regarding age, BSA, QRS duration, QTc interval, or LV hypertrophy. Athletes with the fish-hook sign had higher septal E' velocities and lateral E' velocities compared with athletes who did not. In addition, athletes who had the fish-hook sign had lower E/E' velocities compared with those without. Furthermore, there were nonsignificant differences in LV dimensions and atrial dimensions. The association between the fish-hook sign and the increased peak early E' velocity can be explained by the increased vagal activity in trained athletes, which causes J-point elevation and enhances diastolic filling of the heart. In addition, Baek et al.[18] found a significant relationship between presence of both a J-wave and a slow heart rate and increased vagal activity in patients without structural heart diseases.

Previous cross-sectional studies have demonstrated differences in LV diastolic function between athletes and controls. Pluim et al.[19] reported that the E/A was either normal or slightly, but not significantly, enhanced in athletes compared with controls. Another study reported the enhanced E/A in athletes as being related to a diminished resting heart rate[20]. Likewise, recent, cross-sectional data from a study of LV septal or lateral wall motion in athletes by using TDI showed increased E' and reduced A' tissue velocities compared with controls [21–24].

The present study found that about 16% of the participants had isolated LV ECG voltage criteria. However, echocardiographic assessment found that only five (8%) players had increased LV mass index. These results are in agreement with those of Noseworthy et al.[25], who reported that ER was not associated with concentric or eccentric LV hypertrophy on ECG, suggesting that ER reflects cardiac electric remodeling that occurs independently of the structural remodeling frequently found in athletes' hearts. However, Biasco et al.[26] found a significant correlation between J-point elevation and interventricular septal thickness in athletes and suggested a mechanistic role of exercise-induced hypertrophy as the basis for J-point elevation. A significant change in the latest guidelines of the European Society of Cardiology identifies with the treatment of isolated QRS voltage criteria for LV hypertrophy. Using the former criteria of LV enlargement, most athletes with ECGs designated as abnormal showed isolated increments in QRS voltage. Because of this and other confirmations that such isolated voltage is inadequate to indicate LV mass in athletes[27], it is now accepted that unless there are other markers including deviation of the axis, changes in repolarization, atrial enlargement, or expanded QRS width that indicate actual LV hypertrophy, high QRS voltage is not an adequate reason to select an athlete for further assessment[28],[29].

 Conclusion



Athletes whose ECGs showed fish-hook signs had higher peak early diastolic mitral annular E' velocities and lower E/E' ratios than athletes whose ECGs did not show fish-hook signs.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Uberoi A, Stein R, Perez MV, Freeman J, Wheeler M, Dewey F, et al. Interpretation of the electrocardiogram of young athletes. Circulation 2011; 124:746–757.
2Patton KK, Ellinor PT, Ezekowitz M, Kowey P, Lubitz SA, Perez M, et al. Ascientific statement from the American Heart Association. Circulation 2016; 133:1520–1529.
3Rosso R, Kogan E, Belhassen B, Rozovski U, Scheinman MM, Zeltser D, et al. J-point elevation in survivors of primary ventricular fibrillation and matched control subjects: incidence and clinical significance. J Am Coll Cardiol 2008; 52:1231–1238.
4Gussak I, Antzelevitch C. Early repolarization syndrome: clinical characteristic and possible cellular and ionic mechanisms. J Electrocardiol 2000; 33:299–309.
5Barbosa EC, Bomfim Ade S, Benchimol-Barbosa PR, Ginefra P. Ionic mechanisms and vectorial model of early repolarization pattern in the surface electrocardiogram of the athlete. Ann Noninvasive Electrocardiol 2008; 13:301–307.
6Cappato R, Furlanello F, Giovinazzo V, Infusino T, Lupo P, Pittalis M, et al. Jwave, QRS slurring, and ST elevation in athletes with cardiac arrest in the absence of heart disease: marker of risk or innocent bystander? Circ Arrhythm Electrophysiol 2010; 3:305–311.
7Antzelevitch C, Yan GX. J wave syndromes. Heart Rhythm 2010; 7:549–558.
8Antzelevitch C, Yan GX, Viskin S. Rationale for the use of the terms J-wave syndromes and early repolarization. J Am Coll Cardiol 2011; 57:1587–1590.
9Perez MV, Friday K, Froelicher V. Semantic confusion: the case of early repolarization and the J point. Am J Med 2012; 125:843–847.
10Sokolow M, Lyon TP. Criteria for the diagnosis of right ventricular hypertrophy using unipolar limb and precordial leads. Am J Med 1947; 3:125–126.
11Lang RM, Badano LP, Mor-Avi V, Afilalo J, Armstrong A, Ernande L, et al. Recommendations for cardiac chamber quantification by echocardiography in adults: an update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging. J Am Soc Echocardiogr 2015; 28:1–39.
12Devereux RB, Alonso DR, Lutas EM, Gottlieb GJ, Campo E, Sachs I, et al. Echocardiographic assessment of left ventricular hypertrophy: comparison to necropsy findings. Am J Cardiol 1986; 57:450–458.
13Nagueh SF, Appleton CP, Gillebert TC, Marino PN, Oh JK, Edvardsen T, et al. Recommendations for the evaluation of left ventricular diastolic function by echocardiography. Eur J Echocardiogr 2009; 10:165–193.
14Giannaki CD, Oxborough D, George K. Diastolic Doppler flow and tissue Doppler velocities during, and in recovery from, low-intensity supine exercise. Appl Physiol Nutr Metab 2008; 33:896–902.
15Perez M, Fonda H, Le VV, Mitiku T, Ray J, Freeman JV, et al. Adding an electrocardiogram to the preparticipation examination in competitive athletes: a systematic review. Curr Probl Cardiol 2009; 34:586–662.
16Rautaharju PM, Surawicz B, Gettes LS, Bailey JJ, Childers R, Deal BJ, et al. AHA/ACCF/HRS recommendations for the standardization and interpretation of the electrocardiogram: part IV: the ST segment, T and U waves, and the QT interval: a scientific statement from the American Heart Association Electrocardiography and Arrhythmias Committee, Council on Clinical Cardiology; the American College of Cardiology Foundation; and the Heart Rhythm Society: endorsed by the International Society for Computerized Electrocardiology. J Am Coll Cardiol 2009; 53:982–991.
17Crouse SF, Meade T, Hansen BE, Green JS, Martin SE Electrocardiograms of collegiate football athletes. Clin Cardiol 2009; 32:37–42.
18Baek YS, Park SD, Lee MJ, Kwon SW, Shin SH, Woo SI, et al. Relationship between J waves and vagal activity in patients who do not have structural heart disease. Ann Noninvasive Electrocardiol 2015; 20:464–673.
19Pluim BM, Zwinderman AH, van der Laarse A, van der Wall EE. The athlete's heart. A meta-analysis of cardiac structure and function. Circulation 2001; 101:336–344.
20Kneffel Z, Varga-Pinter B, Toth M, Major Z, Pavlik G. Relationship between heart rate and E/A ratio in athletic and non-athletic males. Acta Physiol Hung 2011; 98:284–293.
21Baldi JC, McFarlane K, Oxenham HC, Whalley GA, Walsh HJ, Doughty RN, et al. Left ventricular diastolic filling and systolic function of young and older trained and untrained men. J Appl Physiol 2003; 95:2570–2575.
22Poh KK, Ton-Nu TT, Neilan TG, Tournoux FB, Picard MH. Myocardial adaptation and efficiency in response to intensive physical training in elite speedskaters. Int J Cardiol 2008; 126:346–351.
23Vinereanu D, Florescu N, Sculthorpe N, Tweddel AC, Stephens, Fraser AG. Left ventricular long-axis diastolic function is augmented in the hearts of endurance-trained compared with strength trained athletes. Clin Sci 2002; 103:249–257.
24Zoncu S, Pelliccia A, Mercuro G. Assessment of regional systolic and diastolic wall motion velocities in highly trained athletes by pulsed wave Doppler tissue imaging. J Am Soc Echocardiogr 2002; 15:900–905.
25Noseworthy PA, Weiner R, Kim J, Keelara V, Wang F, Berkstresser B, et al. Early repolarization pattern in competitive athletes: clinical correlates and the effects of exercise training. Circ Arrhythm Electrophysiol 2011; 4:432–440.
26Biasco L, Cristoforetti Y, Castagno D, Giustetto C, Astegiano P, Ganzit G, et al. Clinical, electrocardiographic, echocardiographic characteristics and long-term follow-up of elite soccer players with J-point elevation. Circ Arrhythm Electrophysiol 2013; 6:1178–1184.
27Rawlins J, Carre F, Kervio G, Papadakis M, Chandra N, Edwards C, et al. Ethnic differences in physiological cardiac adaptation to intense physical exercise in highly trained female athletes. Circulation 2010; 121:1078–1085.
28Ashley EA, Raxwal VK, Froelicher VF. The prevalence and prognostic significance of electrocardiographic abnormalities. Curr Probl Cardiol 2000; 25:1–72.
29Hsieh BP, Pham MX, Froelicher VF. Prognostic value of electrocardiographic criteria for left ventricular hypertrophy. Am Heart J 2005; 150:161–167.