As we gaze into the horizon of the heroin rehab industry, one cannot help but recognize the significant evolution that has been taking place. This metamorphosis is primarily driven by a fundamental shift in perception, from seeing addiction as a moral failing to understanding it as a disease – a chronic but treatable one at that. The future of heroin rehab thus holds immense promise, with an increasing number of advancements and trends shaping the landscape.

The first prediction that seems highly plausible is that the opioid epidemic will continue to encourage the growth of the rehab industry. The United States, in particular, has been grappling with a severe heroin crisis that has claimed numerous lives and wrought socio-economic devastation. Given this, there is an urgent need to propel the industry forward and ensure that effective treatment options are accessible and affordable.

The prediction of growth is not merely speculative. Recent legislative measures, such as the Mental Health Parity and Addiction Equity Act (MHPAEA) of 2008, have already mandated insurance companies to provide coverage for substance abuse treatment. As a result, the rehab industry has witnessed a rapid influx of patients seeking help for heroin addiction.

Furthermore, the future will likely see an increasing emphasis on personalized treatment plans. Substance abuse treatment has traditionally followed a 'one-size-fits-all' approach. However, this method often overlooks the complexity of addiction and the myriad factors that contribute to it – including genetics, socio-economic status, comorbid mental health disorders, and past traumas.

Advancements in fields like genomics and neuroimaging can assist in tailoring treatment plans to individual needs. The concept of personalized medicine, hitherto predominantly associated with fields like oncology, could become a mainstay in heroin rehab. Genomic studies can uncover genetic variations that predispose individuals to addiction, while neuroimaging can identify structural and functional changes in the brain that perpetuate drug-seeking behavior. Integrating these findings can help develop an individualized treatment strategy that maximizes treatment efficacy while minimizing side effects.

Digital technologies are also set to play a pivotal role in the future of heroin rehab. The advent of telemedicine, wearable tech, and smartphone applications offer innovative routes to improving treatment access, adherence, and outcomes. For instance, telemedicine can overcome geographic and socio-economic barriers to treatment. It can also provide continuous care and support, which is crucial given the chronic nature of addiction.

On the other hand, wearable tech and smartphone applications can aid in monitoring drug use and predicting relapses. They can provide real-time data on physiological changes that precede a drug-use episode and trigger timely interventions. These digital tools can also deliver cognitive-behavioral therapy and mindfulness exercises, which are proven strategies for relapse prevention.

While these advancements offer exciting possibilities, they also present challenges. For instance, the increasing digitization of heroin rehab raises concerns about data privacy and security. Balancing the need for comprehensive patient data to inform treatment decisions with the need to protect patient privacy will be a critical issue.

Additionally, while personalized medicine promises improved treatment outcomes, it also requires an understanding of complex genomic and neuroimaging data. Translating these data into clinical practice will necessitate collaboration between scientists, clinicians, and health policymakers.

To conclude, the future of heroin rehab is poised for transformation, driven by an evolving understanding of addiction, the increasing recognition of the need for personalized treatment, and the integration of digital technologies. However, realizing this future will require careful navigation of the challenges that lie ahead. Nevertheless, the potential rewards – in terms of improved treatment outcomes and lives salvaged from the clutches of addiction – are undoubtedly worth the effort.