title: LAD coronary artery myocardial bridging and apical ballooning syndrome.
abstract: OBJECTIVE
  This study sought to evaluate the prevalence and potential role of myocardial bridging in the pathogenesis of apical ballooning syndrome (ABS).
  
  
  BACKGROUND
  ABS is characterized by reversible left ventricular dysfunction, frequently precipitated by a stressful event, but the pathogenesis remains still unclear.
  
  
  METHODS
  Forty-two consecutive patients (40 female, mean age 66 ± 7 years) with ABS underwent echocardiography, cardiac magnetic resonance, coronary angiography (CA) with intravascular ultrasound, and computed tomography angiography (CTA). Myocardial bridging was diagnosed by CA when a dynamic compression phenomenon was observed in the coronary artery and by CTA when a segment of coronary artery was completely (full encasement) or incompletely (partial encasement) surrounded by the myocardium. The prevalence of myocardial bridging detected by CTA and CA in ABS patients was compared with 401 controls without ABS who underwent both CTA and CA.
  
  
  RESULTS
  Myocardial bridging by CTA was observed in 32 ABS patients (76%): 23 with partial encasement and 9 with full encasement. All myocardial bridging was located in the mid segment of the left anterior descending coronary artery (LAD) with a mean length of 17 ± 9 mm. CA revealed myocardial bridging in 17 subjects (40%) (9 with partial encasement and 8 with full encasement by CTA). All subjects in which dynamic compression was observed by CA showed myocardial bridging by CTA, while none of the subjects with negative findings for myocardial bridging by CTA revealed dynamic compression by CA. Compared with controls, ABS patients showed a significant higher prevalence of myocardial bridging in the LAD either by CA (40% vs. 8%; p < 0.001) or by CTA (76% vs. 31%; p < 0.001).
  
  
  CONCLUSIONS
  Our study showed that myocardial bridging of the LAD is a frequent finding in ABS patients as revealed both by CA and, mostly, by CTA, suggesting a role of myocardial bridging as potential substrate in the pathogenesis of ABS.
authors: Department of Cardiac, Thoracic and Vascular Sciences, University of Padova, Padova, Italy.
authors: Federico
authors: F
authors: Migliore
authors: Erica
authors: E
authors: Maffei
authors: Martina
authors: M
authors: Perazzolo Marra
authors: Claudio
authors: C
authors: Bilato
authors: Massimo
authors: M
authors: Napodano
authors: Francesco
authors: F
authors: Corbetti
authors: Alessandro
authors: A
authors: Zorzi
authors: Anto Luigi
authors: AL
authors: Andres
authors: Cristiano
authors: C
authors: Sarais
authors: Luisa
authors: L
authors: Cacciavillani
authors: Enrico
authors: E
authors: Favaretto
authors: Chiara
authors: C
authors: Martini
authors: Sara
authors: S
authors: Seitun
authors: Filippo
authors: F
authors: Cademartiri
authors: Domenico
authors: D
authors: Corrado
authors: Sabino
authors: S
authors: Iliceto
authors: Giuseppe
authors: G
authors: Tarantini
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D017023:Coronary Angiography / Q000379:methods; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D054084:Myocardial Bridging / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D011237:Predictive Value of Tests; D015995:Prevalence; D011446:Prospective Studies; D054549:Takotsubo Cardiomyopathy / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D018084:Ultrasonography, Interventional; D016277:Ventricular Function, Left