The ornamental design for a heartratevariabilityanalyzer, as shown and described.
FIG. 1 is a top perspective of a heart rate variability analyzer showing my new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken lines in the drawing views are included for the purpose of illustrating portions of the heart rate variability analyzer that form no part of the claimed design.