Doppler echocardiography underestimates the prevalence
and magnitude of mid-cavity obstruction in patients with
symptomatic hypertrophic cardiomyopathy
James W. Malcolmson
Stephen M. Hamshere
Steffen E. Petersen
Saidi A. Mohiddin
Barts Heart Centre, Barts Health NHS
Trust, Whitechapel, London E1 1BB, United
William Harvey Research Institute, Queen
Mary University of London, United Kingdom
NIHR Biomedical Research Unit at Barts,
London, United Kingdom
UCL Centre for Heart Muscle Disease,
Institute of Cardiovascular Science,
University College London, Gower St,
London WC1E, United Kingdom
Saidi Mohiddin, Barts Heart Centre, No 1,
St Martins Le Grand, London, EC1A 4AS,
Objectives: To evaluate utility of Doppler echocardiography in the assessment of left ventricular
(LV) mid-cavity obstructive (LVMCO) hypertrophic cardiomyopathy (HCM).
Background: LVMCO is a relatively under-diagnosed complication of HCM and may occur alone
or in combination with LV outflow tract obstruction (LVOTO). Identifying and quantifying LVMCO
and differentiating it from LVOTO has important implications for patient management. We aimed
to assess diagnostic performance of Doppler echocardiography in the assessment of suspected LV
Methods: Forty symptomatic HCM patients with suspected obstruction underwent cardiac
catheterization, and comparison of location and magnitude of Doppler derived gradients with
synchronous invasive measurements (reference standard), at rest and isoprenaline stress (IS).
Results: Doppler’s diagnostic accuracy for any obstruction (30 mmHg) in this cohort was 75%
with false positive and false negative rates of 2.5 and 22.5%, respectively. During subanalysis,
Doppler’s diagnostic accuracy for isolated LVOTO in this selected cohort is 83% with false positive
and false negative rates of 4 and 12.5%, respectively. For LVMCO, the accuracy is only 50%, with
false positive and false negative rates of 10 and 40%, respectively.
Doppler gradients for isolated LVOTO were similar to invasive: 85 6 51 and 87 6 35 mmHg,
respectively (P 5 0.77). Doppler gradients in LVMCO were consistently lower than invasive: 45 6
38 and 81 6 31 mmHg, respectively (P 5 0.0002). Mid-systolic flow cessation and/or contamina-
tion of spectral signals were identified as causes of Doppler-derived inaccuracies.
Conclusions: Doppler echocardiography under-diagnoses and underestimates severity of LVMCO
in symptomatic HCM patients. Recognition of abrupt mid-systolic flow cessation and invasive
measurements may improve detection of LVMCO in HCM.
Doppler echocardiography, hypertrophic cardiomyopathy, mid-cavity, obstruction
Relationships with industry: None declared
Catheter Cardiovasc Interv. 2018;91:783–789. wileyonlinelibrary.com/journal/ccd
2017 Wiley Periodicals, Inc.
Received: 16 September 2016
Revised: 4 April 2017
Accepted: 3 May 2017