Dynamic Handgrip Exercise: Feasibility and Physiologic Stress Response of a Potential Needle-Free Cardiac Magnetic Resonance Stress Test

Abstract

Background: Cardiac magnetic resonance (CMR) pharmacological stress-testing is a well-established technique for detecting myocardial ischemia. Although stressors and contrast agents seem relatively safe, contraindications and side effects must be considered. Substantial costs are further limiting its applicability. Dynamic handgrip exercise (DHE) may have the potential to address these shortcomings as a physiological stressor. We therefore evaluated the feasibility and physiologic stress response of DHE in relation to pharmacological dobutamine-stimulation within the context of CMR examinations.Methods: Two groups were prospectively enrolled: (I) volunteers without relevant disease and (II) patients with known CAD referred for stress-testing. A both-handed, metronome-guided DHE was performed over 2 min continuously with 80 contractions/minute by all participants, whereas dobutamine stress-testing was only performed in group (II). Short axis strain by fast-Strain-ENCoded imaging was acquired at rest, immediately after DHE and during dobutamine infusion.Results: Eighty middle-aged individuals (age 56 ± 17 years, 48 men) were enrolled. DHE triggered significant positive chronotropic (HRrest: 68 ± 10 bpm, HRDHE: 91 ± 13 bpm, p < 0.001) and inotropic stress response (GLSrest: −19.4 ± 1.9%, GLSDHE: −20.6 ± 2.1%, p < 0.001). Exercise-induced increase of longitudinal strain was present in healthy volunteers and patients with CAD to the same extent, but in general more pronounced in the midventricular and apical layers (p < 0.01). DHE was aborted by a minor portion (7%) due to peripheral fatigue. The inotropic effect of DHE appears to be non-inferior to intermediate dobutamine-stimulation (GLSDHE= −19.5 ± 2.3%, GLSDob= −19.1 ± 3.1%, p = n.s.), whereas its chronotropic effect was superior (HRDHE= 89 ± 14 bpm, HRDob= 78 ± 15 bpm, p < 0.001).Conclusions: DHE causes positive ino- and chronotropic effects superior to intermediate dobutamine-stimulation, suggesting a relevant increase of myocardial oxygen demand. DHE appears to be safe and timesaving with broad applicability. The data encourages further studies to determine its potential to detect obstructive CAD.

Safety of dobutamine or adenosine stress cardiac magnetic resonance imaging in patients with left ventricular thrombus

“…However, the use of contrast agents is not part of a clinical routine in our hospital and was not done in our study patients. Lastly, our study only assessed drug-induced stress tests and new stressors like dynamic handgrip exercises or hyperventilation were not analysed [ 57 – 60 ].…”

Safety, accuracy, and prediction of prognosis in patients with end-stage chronic kidney disease undergoing dobutamine stress cardiac magnetic resonance imaging

“…Considering the overall risk of NSF with modern macrocyclic GBCAs (estimated at <0.07%), the usage of perfusion CMR is worth discussing. Apart from that, other medication-and contrast-free CMR protocols have currently been evaluated and might serve as a valuable alternative in patients with CKD (39)(40)(41)(42).…”

Complications of exercise and pharmacologic stress echocardiography

“…Diagnostic endpoints include a heart rate goal of ≥85% of maximum predicted heart rate (MPHR), limiting severe chest pain or anginal equivalent, or positivity via electrocardiographic (ECG) criteria. In patients with limited mobility, alternative exercise protocols that have been utilized include upper extremity maneuvers via handgrip exercise (11)(12)(13)(14) or via cycle ergometer (15)(16)(17). Though data is limited, static active leg lifts may be considered as an alternative exercise modality as well (18).…”