Process-aware information systems (PAIS) offer promising perspectives in this respect and are increasingly employed for operationally supporting business processes. In this paper, we describe the emergence of different process support paradigms and the lack of methods for comparing existing change approaches have made it difficult for process-aware software architecture (PASA) engineers to choose the adequate technology. A pattern-based analysis combines self-adapting and self-evolution theory in PAIS, we adopt a set of changes patterns and change support features to put forwards four kinds of model of PASA according to the situation of the needs business processer facing and changeable environment. Based on these change patterns and features, we provide a detailed mechanism analysis and case study evaluation in the healthcare industry of the relationship between cross-organizational dynamic process-aware software architecture (CD-PASA) and change patterns of business processes. In summary, we identified change patterns and change support features facilitate the comparison of change support frameworks, and consequently will support PASA engineers in selecting the right technology for realizing flexible PASA. In addition, this work can be used as a reference for implementing more flexible PASA.