From:  Left ventricular hemodynamic forces: gaining insight into left ventricular function

 Summary of the published studies on HDF

Study populationMethodParametersPeriod of the cardiac cycle analyzedFindings (as reported in the abstract of the article)Reference
Healthy subjects, DCMCMRSax-max/Lax-max force ratioEntire diastole; early filling phase; late filling phaseThe LV hemodynamic filling forces showed a similar temporal progression among healthy subjects, whereas DCM patients had forces that were more heterogeneous in their direction and magnitude during diastole[16]
Healthy volunteers/athletesCMRPeak values; average amplitude (RMS); early diastolic filling impulseFirst third of systole; middle third of early filling; final third of atrial contraction; systole; diastole; E-wave; A-waveForce patterns were similar between healthy subjects and athletes, indicating potential utility as a cardiac function biomarker[10]
Heart failure with LBBBCMRSax-max force/Lax-max force; average amplitude (RMS)Entire diastole; early filling phase; late filling phaseHDF may serve as an additional tool for considering the risks imposed by conduction abnormalities in heart failure patients and prove to be useful in predicting response to CRT[13]
CRTEchoRMS longitudinal; RMS transversal; RMS transversal/RMS longitudinalEntire cardiac cyclePacing-induced realignment of HDFs is associated with CRT efficacy at follow-up[22]
Heart failureCMRAverage amplitude (RMS); peak forces; in the transverse plane and the apical-to-basal directionEntire cardiac cycleLV hemodynamic forces noninvasively computed using the newly developed mathematic model may significantly improve the detection of early myocardial systolic dysfunction when volumetric and deformation cardiac measures are still intact[12]
Healthy volunteersEchoAverage amplitude (RMS); LV impulse (AUC)Entire cardiac cycle; systolic phase; LV suctionThis approach could differentiate normality from pathology by providing average HDF parameters, differentiated by age and gender[7]
Healthy volunteersEchoLongitudinal; transverse; systolic impulse (AUC); systolic peak of the longitudinal forces; average amplitude (RMS); angle (orientation)Entire cardiac cycle; systole; diastoleKnowledge of the physiologic range of LV HDF may prompt their implementation into the clinical routine and allow a more comprehensive assessment of the LV function[9]
Diastolic dysfuntionEchoMean amplitude of the longitudinal forces (RMS)DiastoleA scoring system including HDFs might improve the accuracy of echocardiography in estimating LV filling pressures[26]
HFpEFCMRAverage amplitude (RMS); peak forces; in the transverse plane and the apical-to-basal directionEntire cardiac cycle; systole; diastole; with/without volume normalizationLV hemodynamic force analysis, whether indexed to LV volumes or not, is not ready for clinical trials on HFpEF assessment[15]
Post-MICMRAverage amplitude (RMS); longitudinal (A-B) HDFs; horizontal (L-S) HDFs; L-S/A-B HDFs ratio; angle (orientation)Entire cardiac cycle; systole; diastoleMisalignment of diastolic hemodynamic forces after STEMI is associated with adverse LV remodeling after 4 months[23]
HFrEFEchoAverage amplitude (RMS); longitudinal (A-B) HDFs; horizontal (L-S) HDFs; L-S/A-B HDFs ratio; angle (orientation)Entire cardiac cycle; systole; diastoleIn patients with HFrEF, therapy with sacubitril/valsartan improves HDF distribution[28]
HFpEFCMRAverage amplitude (RMS); peak systolic HDF; systolic impulse (AUC); systolic–diastolic transition (LV deceleration and LV suction)Entire cardiac cycle; early diastolic filling/diastolic deceleration; late diastolic filling/atrial thrust; early diastolic filling/late diastolic fillingAssessment of HDF indicates impairment of LV systolic ejection force in HFpEF which is associated with cardiovascular events[14]
CRTCMRAverage amplitude (RMS); A-B strength; L-S strength; I-A strengthEntire cardiac cycle; systole; diastoleHDF parameters can predict the response to CRT in heart failure patients, aiding in the selection of candidates who are more likely to benefit from the therapy[21]
CRTEchoAverage amplitude (RMS); A-B strength; L-S strength; L-S/A-B ratio; angle (orientation); systolic impulse (AUC)Entire cardiac cycle; systolic thrustHDF in CRT recipients reflect the acute effect of CRT and the effect of LV reverse remodeling on intraventricular pressure gradients. Whether HDF analysis provides incremental value over established Echo parameters, remains to be determined[19]
Dilated cardiomyopathyCMRIVPGEntire cardiac cycle; systolic ejection; isovolumic relaxation; E-wave deceleration; A-wave accelerationIn the absence of pressure reversal, lower systolic ejection force, E-wave decelerative force, and overall LV-IVPG are powerful predictors of outcome, independent of clinical and imaging parameters[17]
After TAVIEchoAverage amplitude (RMS); angle (orientation); systolic impulse (AUC); time from R wave to peak systole; time of transition; time from the start of relaxation to positive peak of diastolicEntire cardiac cycle; systolic phase; transition; suctionEcho analysis of HDFs could help differentiate patients with LV function recovery after TAVI from patients with persistent hemodynamic dysfunction[25]
CRTEchoAverage amplitude (RMS); A-B strength; L-S strength; angle (orientation); systolic impulse (AUC)Entire cardiac cycle; systolic thrustSix months after CRT, the orientation of HDF improves in LV responders and LV non-responders, while the magnitude of A-B HDF only improves in LV responders[19]
Healthy volunteersCMRAverage amplitude (RMS); L-S/A-B HDF ratio; LV impulse (AUC)Entire cardiac cycle; systole; diastole; systolic/diastolic transition; diastolic deceleration; atrial thrustThe study provided comprehensive normal values of HDF assessments with specific age and sex stratification[8]
Post-aortic coarctation repairEchoAverage amplitude (RMS); LV impulse (AUC)Entire cardiac cycle; systolic phase; LV suctionPatients with coarctation of the aorta had lower LV myocardial strain and HDF parameters values, independently associated with hospitalization for heart failure[24]
Athletes, hypertensive patientsCMRAverage amplitude (RMS); longitudinal (A-B) HDFs; horizontal (L-S) HDFs; L-S/A-B HDFs ratio; angle (orientation); hemodynamic work (AUC); peak; durationEntire cardiac cycle; systolic phase; suction; early LV filling; atrial thrustHDF allows distinction between the hemodynamic patterns of athletes and patients with hypertension[11]
Non-ischemic LV cardiomyopathyCMRUnsupervised clustering of longitudinal and transversal HDFEntire cardiac cycleAnalyzing both longitudinal and transversal HDF throughout the cardiac cycle enables the identification of distinct phenotypes with prognostic value beyond EF and LGE in non-ischemic LV cardiomyopathy[18]

A-B: apical-basal; AUC: area under the curve; CMR: cardiac magnetic resonance; CRT: cardiac resynchronization therapy; DCM: dilated cardiomyopathy; Echo: echocardiographic; EF: ejection fraction; HDF: hemodynamic forces; HFpEF: heart failure with preserved ejection fraction; HFrEF: heart failure with reduced ejection fraction; I-A: inferior-anterior; IVPG: intraventricular pressure gradients; L-S: lateral-septal; LBBB: left bundle branch block; LGE: late gadolinium enhancement; LV: left ventricular; RMS: root mean square; STEMI: S-T segment elevation myocardial infarction; TAVI: transcatheter aortic valve implantation