High-grade video compression of echocardiographic studies: a multicenter validation study of selected motion pictures expert groups (MPEG)-4 algorithms

Near real-time echocardiography teleconsultation using low bandwidth and MPEG-4 compression: feasibility, image adequacy and clinical implications

We assessed the feasibility, image adequacy and clinical utility of a tele-echocardiography service which combined video compression with low-bandwidth store-and-forward transmission. Echocardiograms were acquired by a hospital geriatrician, compressed and transmitted using both near real-time (urgent) and delayed (pre-programmed) protocols via an Internet connection to the notebook PC of a remote cardiologist. Clinical utility was evaluated as a change in therapeutic management. During a one-year period, 101 tele-echocardiography consultations were successfully performed (feasibility = 100%) on 95 patients (age 22-95 years), admitted with cardiovascular or neurological diagnoses (24% of the consultations were urgent). In total, 4617 files (1.4 GByte of data) were transmitted, 2669 of which were short video clips. On average, 46 files (13.8 MByte) were transmitted (mean duration 10 min) at each examination. Consultations (both urgent and pre-programmed) were clinically useful in 83% of examinations. Logistic regression analysis showed that both a low left ventricular systolic function and the examination indication were determinants of clinical utility. The transmitted images were considered adequate for diagnosis in 100% of the pre-programmed teleconsultations. Tele-echocardiography using MPEG-4 video compression is a feasible, adequate and clinically useful tool for telemedicine.

Second-opinion stress tele-echocardiography for the Adonhers (Aged donor heart rescue by stress echo) project

BACKGROUND

To resolve the current shortage of donor hearts, we established the Adonhers protocol. An upward shift of the donor age cut-off limit (from the present 55 to 65 years) is acceptable if a stress echo screening on the candidate donor heart is normal. This study aimed to verify feasibility of a "second opinion" of digitally transferred images of stress echo results to minimize technical variability in selection of aged donor hearts for heart transplant.

METHODS

The informatics infrastructure was created for a core lab reading with a second opinion from the Pisa stress echo lab. To test the system, simulation standard stress echo cineloops were sent digitally from 5 peripheral labs to the central core lab.Starting January 2009, real marginal donor stress echos were sent via internet to the central core echo lab, Pisa, for a second opinion before heart transplant.

RESULTS

In the simulation protocol, 30 dipyridamole stress echocardiograms were sent from the five peripheral echo labs to the central core lab in Pisa. Both the echo images and reports were correctly uploaded in the web system and sent to the core echo lab; the second opinion evaluation was obtained in all cases (100% feasibility). In the transplant protocol, eight donor cases were sent to the Pisa core lab for the second opinion protocol, and six of them were transplanted in marginal recipients.

CONCLUSIONS

Second-Opinion Stress Tele-Echocardiography can effectively be performed in a network aimed to safely expand the heart donor pool for heart transplant.