There is a new indepth article which is extremely well referenced. IT is an overveiw of the current understanding of the role of CPn in atherosclerosis. their conclusion quoted here:
The idea that infections contribute to atherosclerotic plaque development and CVD is not a new concept, but it is one that is extremely difficult to prove categorically. As with other multifactorial, chronic disease processes, the situation is immensely complicated, and probably no single experiment will prove or disprove the hypothesis. A large body of associative and correlative evidence exists for the involvement of C. pneumoniae infection in some aspects of the acceleration of CVD. This accumulation of evidence is perhaps the best answer that can be found at this time. The involvement of an infectious agent in the progression of a disease rather than the initiation aetiology represents a subtle shift in the infectious disease paradigm but is probably an accurate assessment of the role of C. pneumoniae in CVD. Clearly, well-defined studies on bacterial pathogenesis will add to this body of evidence in important ways. The identification and implementation of immunological or therapeutic strategies that result in eradication of the organism in both respiratory and cardiovascular sites may be the only way to answer the question irrefutably.
The link is here: http://www.blackwell-synergy.com/doi/full/10.1046/j.1462-5822.2003.00352.x?cookieSet=1