Identifying how the body responds to expressive changes is key to understanding how music influences cardiovascular and respiratory variables. Neuroscience has explored brain processing of acoustic boundaries, but little is known about peripheral physiological responses. Rather than treating entire music pieces as uniform stimuli, this study considers expressive change points in music as micro-interventions for eliciting specific responses. The goal is to link expressive music variations to changes in cardiovascular signals to uncover how the body reacts to time-varying musical structures. Synchronised musical and physiological data were collected from 80 participants during a 5-minute silence baseline and 40-minute of listening to 9 rendered performances. A total of 754 musical change points were identified algorithmically from acoustic/MIDI signals and through expert annotations. Physiological change points were derived from respiratory and RR intervals, blood pressure signals, and HRV spectral parameters. These were converted to time series using Gaussian Kernel functions. We then applied Canonical Correlation Analysis (CCA) to extract maximally correlated pairs of canonical variates (linear combinations of variables from each domain) to determine the relationships between the musical and physiological change points. The CCA's first two canonical variate pairs showed significant canonical correlations (0.53 and 0.38) compared to surrogate data. High canonical loadings (>|+/-0.5|) indicated an increase in respiratory frequency linked with novel melodies and tempo changes, and a decrease in RR intervals with increased loudness and acoustic energy. Subgroup analysis revealed that these associations were modulated by baseline autonomic activity and the presence of elevated BP (>140/90 mmHg), indicating that individual physiological traits influence patterns of response to expressive music changes. These findings suggest that localised musical events can serve as targeted micro-interventions, enabling personalised adjustments of cardiovascular variables, laying the groundwork for tailored music-based therapies in cardiovascular theranostics, integrating diagnostic and therapeutic approaches.