regex101: 3

Regular Expression

(?<=alt=\")(.*?)(?=\"><)

New

<div data-video-id="a6afa8d5-cb1f-e4b1-02e2-e74c8943fea6" data-video-url="https://iframe.dacast.com/vod/acae82153ef4d7a7344ae4eaa86af534/a6afa8d5-cb1f-e4b1-02e2-e74c8943fea6" data-video-poster="https://universe-files.dacast.com/87aad1e1-8fe7-96b0-3071-2ef62f5e797f" data-ads="[]" data-ads-min-time="10" class="ec-lecture-item-row ec-library-tile-js ec-congress-hover"><div class="ec-lecture-info"><div class="item item-number"> 1 </div><div class="item item-img"><div class="item-img-container"><img src="https://universe-files.dacast.com/87aad1e1-8fe7-96b0-3071-2ef62f5e797f" alt="1_1 - DICOM, HL7, IHE: from zero to hero"></div></div><div class="item item-description ec-flex-row"><div><h4>1_1 - DICOM, HL7, IHE: from zero to hero</h4><p><span class="icon icon-clock">48:37</span><span class="icon icon-moderator">F. Zanca, Heverlee/BE</span></p></div></div></div><div class="ec-lecture-description"><p></p></div></div><div data-video-id="b63f8367-8f6e-cdcc-0f06-2d8fdb92b8dc" data-video-url="https